Method for transmitting and receiving signal in wireless communication system, and device supporting same

ABSTRACT

A method for transmitting and receiving a signal in a wireless communication system and a device supporting same, according to one embodiment of the present invention, comprise: receiving information for a PUSCH starting symbol #K; and transmitting a PUSCH in a predetermined position on the basis of the result of carrying out a CAP. The predetermined position is determined on the basis of a parameter related to the length of a CPE, and the length of the CPE is less than or equal to the length of an OFDM symbol.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/KR2020/013439, filed on Oct. 5, 2020, which claims the benefit ofearlier filing date and right of priority to Korean Patent ApplicationNos. 10-2019-0141950 filed on Nov. 7, 2019, 10-2020-0028567 filed onMar. 6, 2020, and 10-2020-0041802 filed on Apr. 6, 2020, and also claimsthe benefit of U.S. Provisional Application No. 62/911,176 filed on Oct.4, 2019, the contents of all of which are hereby incorporated byreference herein in their entirety.

TECHNICAL FIELD

The present disclosure relates to a method and apparatus fortransmitting and receiving a signal in a wireless communication system.

BACKGROUND ART

Wireless access systems have been widely deployed to provide varioustypes of communication services such as voice or data. In general, awireless access system is a multiple access system that supportscommunication of multiple users by sharing available system resources (abandwidth, transmission power, etc.) among them. For example, multipleaccess systems include a code division multiple access (CDMA) system, afrequency division multiple access (FDMA) system, a time divisionmultiple access (TDMA) system, an orthogonal frequency division multipleaccess (OFDMA) system, and a single carrier frequency division multipleaccess (SC-FDMA) system.

DISCLOSURE Technical Problem

Provided are a method and apparatus for efficiently performing awireless signal transmission and reception procedure.

It will be appreciated by persons skilled in the art that the objectsthat could be achieved with the present disclosure are not limited towhat has been particularly described hereinabove and the above and otherobjects that the present disclosure could achieve will be more clearlyunderstood from the following detailed description.

Technical Solution

According to a first aspect of the present disclosure, provided hereinis a method performed by a user equipment (UE) in a wirelesscommunication system, including receiving information for a physicaluplink shared channel (PUSCH) starting symbol #K; and transmitting aPUSCH at a specific position based on a result of performing a channelaccess procedure (CAP). The specific position may be determined based ona parameter related to a length of cyclic prefix extension (CPE), andthe length of CPE may be equal to or less than a length of oneorthogonal frequency-division multiplexing (OFDM) symbol.

According to a second aspect of the present disclosure, provided hereinis a user equipment (UE) used in a wireless communication system,including at least one transceiver; at least one processor; and at leastcomputer memory operably connected to the at least one transceiver andthe at least one processor and configured to cause, when executed, theat least one transceiver and the at least one processor to perform anoperation. The operation may include receiving information for aphysical uplink shared channel (PUSCH) starting symbol #K; andtransmitting a PUSCH at a specific position based on a result ofperforming a channel access procedure (CAP). The specific position maybe determined based on a parameter related to a length of cyclic prefixextension (CPE), and the length of CPE may be equal to or less than alength of one orthogonal frequency-division multiplexing (OFDM) symbol.

According to a third aspect of the present disclosure, provided hereinis an apparatus for a user equipment (UE), including at least oneprocessor, and at least memory configured to store one or moreinstructions causing the at least one processor to perform an operation.The operation may include receiving information for a physical uplinkshared channel (PUSCH) starting symbol #K; and transmitting a PUSCH at aspecific position based on a result of performing a channel accessprocedure (CAP). The specific position may be determined based on aparameter related to a length of cyclic prefix extension (CPE), and thelength of CPE may be equal to or less than a length of one orthogonalfrequency-division multiplexing (OFDM) symbol.

According to a fourth aspect of the present disclosure, provided hereinis a processor-readable medium storing one or more instructions whichcause at least one processor to perform an operation. The operation mayinclude receiving information for a physical uplink shared channel(PUSCH) starting symbol #K; and transmitting a PUSCH at a specificposition based on a result of performing a channel access procedure(CAP). The specific position may be determined based on a parameterrelated to a length of cyclic prefix extension (CPE), and the length ofCPE may be equal to or less than a length of one orthogonalfrequency-division multiplexing (OFDM) symbol.

The parameter may be an integer that causes the length of CPE to beequal to or less than the length of one OFDM symbol, and the length ofone OFDM symbol may be a symbol length of the symbol #K.

The length of one OFDM symbol may differ based on a subcarrier spacing(SCS).

The parameter may be determined based on a subcarrier spacing (SCS).

The parameter may be determined based on a type of the CAP.

The length of CPE may be determined based on the parameter and a timingadvance (TA).

The parameter may be a maximum integer that causes the length of CPE notto exceed the symbol length of the symbol #K, based on the parameterbeing not configured by a higher layer signal.

The specific position may be a position earlier than the symbol #K bythe length of CPE.

The PUSCH may be transmitted in an unlicensed band.

The apparatus applied to an embodiment of the present disclosure mayinclude an autonomous driving device.

The above-describe aspects of the present disclosure are merely a partof preferred embodiments of the present disclosure, and those skilled inthe art will derive and understand various embodiments reflectingtechnical features of the present disclosure based on the followingdetailed description of the present disclosure.

Advantageous Effects

According to embodiments of the present disclosure, a signal may beefficiently transmitted and received in a wireless communication system.

According to embodiments of the present disclosure, an efficient signaltransmission method considering the characteristics of an unlicensedband is provided.

According to embodiments of the present disclosure, a PUSCH startingposition may be efficiently determined.

It will be appreciated by persons skilled in the art that the effectsthat can be achieved with the present disclosure are not limited to whathas been particularly described hereinabove and other advantages of thepresent disclosure will be more clearly understood from the followingdetailed description taken in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the disclosure, illustrate embodiments of thedisclosure and together with the description serve to explain theprinciple of the disclosure:

FIG. 1 illustrates physical channels and a general signal transmissionmethod using the physical channels in a 3rd generation partnershipproject (3GPP) system as an exemplary wireless communication system;

FIG. 2 illustrates a radio frame structure;

FIG. 3 illustrates a resource grid during the duration of a slot;

FIG. 4 illustrates exemplary mapping of physical channels in a slot;

FIG. 5 illustrates exemplary uplink (UL) transmission operations of auser equipment (UE);

FIG. 6 illustrates exemplary repeated transmissions based on aconfigured grant;

FIG. 7 illustrates a wireless communication system supporting anunlicensed band;

FIG. 8 illustrates an exemplary method of occupying resources in anunlicensed band;

FIG. 9 illustrates an exemplary channel access procedure of a UE for ULsignal transmission in an unlicensed band applicable to the presentdisclosure;

FIGS. 10 to 13 illustrate signal transmission procedures according to anembodiment of the present disclosure;

FIGS. 14 to 17 illustrate exemplary uplink signal transmission accordingto an embodiment of the present disclosure;

FIG. 18 illustrates initial access to a network and a subsequentcommunication procedure;

FIG. 19 illustrates an exemplary communication system applied to thepresent disclosure;

FIG. 20 illustrates an exemplary wireless device applicable to thepresent disclosure;

FIG. 21 illustrates another exemplary wireless device applicable to thepresent disclosure; and

FIG. 22 illustrates an exemplary vehicle or autonomous driving vehicleapplicable to the present disclosure.

BEST MODE

The following technology may be used in various wireless access systemssuch as code division multiple access (CDMA), frequency divisionmultiple access (FDMA), time division multiple access (TDMA), orthogonalfrequency division multiple access (OFDMA), single carrier frequencydivision multiple access (SC-FDMA), and so on. CDMA may be implementedas a radio technology such as universal terrestrial radio access (UTRA)or CDMA2000. TDMA may be implemented as a radio technology such asglobal system for mobile communications (GSM)/general packet radioservice (GPRS)/enhanced data rates for GSM evolution (EDGE). OFDMA maybe implemented as a radio technology such as institute of electrical andelectronics engineers (IEEE) 802.11 (wireless fidelity (Wi-Fi)), IEEE802.16 (worldwide interoperability for microwave access (WiMAX)), IEEE802.20, evolved UTRA (E-UTRA), and so on. UTRA is a part of universalmobile telecommunications system (UMTS). 3rd generation partnershipproject (3GPP) long term evolution (LTE) is a part of evolved UMTS(E-UMTS) using E-UTRA, and LTE-advanced (LTE-A) is an evolution of 3GPPLTE. 3GPP new radio or new radio access technology (NR) is an evolvedversion of 3GPP LTE/LTE-A.

As more and more communication devices require larger communicationcapacities, the need for enhanced mobile broadband communicationrelative to the legacy radio access technologies (RATs) has emerged.Massive machine type communication (MTC) providing various services tointer-connected multiple devices and things at any time in any place isone of significant issues to be addressed for next-generationcommunication. A communication system design in which services sensitiveto reliability and latency are considered is under discussion as well.As such, the introduction of the next-generation radio access technology(RAT) for enhanced mobile broadband communication (eMBB), massive MTC(mMTC), and ultra-reliable and low latency communication (URLLC) isbeing discussed. For convenience, this technology is called NR or NewRAT in the present disclosure.

While the following description is given in the context of a 3GPPcommunication system (e.g., NR) for clarity, the technical spirit of thepresent disclosure is not limited to the 3GPP communication system. Forthe background art, terms, and abbreviations used in the presentdisclosure, refer to the technical specifications published before thepresent disclosure (e.g., 38.211, 38.212, 38.213, 38.214, 38.300,38.331, and so on).

In a wireless access system, a user equipment (UE) receives informationfrom a base station (BS) on DL and transmits information to the BS onUL. The information transmitted and received between the UE and the BSincludes general data and various types of control information. Thereare many physical channels according to the types/usages of informationtransmitted and received between the BS and the UE.

FIG. 1 illustrates physical channels and a general signal transmissionmethod using the physical channels in a 3GPP system.

When a UE is powered on or enters a new cell, the UE performs initialcell search (S11). The initial cell search involves acquisition ofsynchronization to a BS. For this purpose, the UE receives asynchronization signal block (SSB) from the BS. The SSB includes aprimary synchronization signal (PSS), a secondary synchronization signal(SSS), and a physical broadcast channel (PBCH). The UE synchronizes itstiming to the BS and acquires information such as a cell identifier (ID)based on the PSS/SSS. Further, the UE may acquire information broadcastin the cell by receiving the PBCH from the BS. During the initial cellsearch, the UE may also monitor a DL channel state by receiving adownlink reference signal (DL RS).

After the initial cell search, the UE may acquire more detailed systeminformation by receiving a physical downlink control channel (PDCCH) anda physical downlink shared channel (PDSCH) corresponding to the PDCCH(S12).

Subsequently, to complete connection to the BS, the UE may perform arandom access procedure with the BS (S13 to S16). Specifically, the UEmay transmit a preamble on a physical random access channel (PRACH)(S13) and may receive a PDCCH and a random access response (RAR) for thepreamble on a PDSCH corresponding to the PDCCH (S14). The UE may thentransmit a physical uplink shared channel (PUSCH) by using schedulinginformation in the RAR (S15), and perform a contention resolutionprocedure including reception of a PDCCH and a PDSCH signalcorresponding to the PDCCH (S16).

When the random access procedure is performed in two steps, steps S13and S15 may be performed as one step (in which Message A is transmittedby the UE), and steps S14 and S16 may be performed as one step (in whichMessage B is transmitted by the BS).

After the above procedure, the UE may receive a PDCCH and/or a PDSCHfrom the BS (S17) and transmit a physical uplink shared channel (PUSCH)and/or a physical uplink control channel (PUCCH) to the BS (S18), in ageneral UL/DL signal transmission procedure. Control information thatthe UE transmits to the BS is generically called uplink controlinformation (UCI). The UCI includes a hybrid automatic repeat andrequest acknowledgement/negative acknowledgement (HARQ-ACK/NACK), ascheduling request (SR), channel state information (CSI), and so on. TheCSI includes a channel quality indicator (CQI), a precoding matrix index(PMI), a rank indication (RI), and so on. In general, UCI is transmittedon a PUCCH. However, if control information and data should betransmitted simultaneously, the control information and the data may betransmitted on a PUSCH. In addition, the UE may transmit the UCIaperiodically on the PUSCH, upon receipt of a request/command from anetwork.

FIG. 2 illustrates a radio frame structure.

In NR, UL and DL transmissions are configured in frames. Each radioframe has a length of 10 ms and is divided into two 5-ms half-frames.Each half-frame is divided into five 1-ms subframes. A subframe isdivided into one or more slots, and the number of slots in a subframedepends on a subcarrier spacing (SCS). Each slot includes 12 or 14OFDM(A) symbols according to a cyclic prefix (CP). When a normal CP isused, each slot includes 14 OFDM symbols. When an extended CP is used,each slot includes 12 OFDM symbols. A symbol may include an OFDM symbol(or a CP-OFDM symbol) and an SC-FDMA symbol (or a discrete Fouriertransform-spread-OFDM (DFT-s-OFDM) symbol).

Table 1 exemplarily illustrates that the number of symbols per slot, thenumber of slots per frame, and the number of slots per subframe varyaccording to SCSs in a normal CP case.

TABLE 1 SCS (15*2{circumflex over ( )}u) N_(symb) ^(slot) N_(slot)^(frame,u) N_(slot) ^(subframe,u)  15 KHz (u = 0) 14 10 1  30 KHz (u= 1) 14 20 2  60 KHz (u = 2) 14 40 4 120 KHz (u = 3) 14 80 8 240 KHz (u= 4) 14 160 16 *N_(symb) ^(slot): number of symbols in a slot *N_(slot)^(frame,u): number of slots in a frame *N_(slot) ^(subframe,u): numberof slots in a subframe

Table 2 illustrates that the number of symbols per slot, the number ofslots per frame, and the number of slots per subframe vary according toSCSs in an extended CP case.

TABLE 2 SCS (15*2{circumflex over ( )}u) N_(symb) ^(slot) N_(slot)^(frame,u) N_(slot) ^(subframe,u) 60 KHz (u = 2) 12 40 4

The frame structure is merely an example, and the number of subframes,the number of slots, and the number of symbols in a frame may be changedin various manners.

In the NR system, different OFDM(A) numerologies (e.g., SCSs, CPlengths, and so on) may be configured for a plurality of cellsaggregated for one UE. Accordingly, the (absolute time) duration of atime resource (e.g., a subframe, a slot, or a transmission time interval(TTI)) (for convenience, referred to as a time unit (TU)) composed ofthe same number of symbols may be configured differently between theaggregated cells.

In NR, various numerologies (or SCSs) may be supported to supportvarious 5th generation (5G) services. For example, with an SCS of 15kHz, a wide area in traditional cellular bands may be supported, whilewith an SCS of 30 kHz or 60 kHz, a dense urban area, a lower latency,and a wide carrier bandwidth may be supported. With an SCS of 60 kHz orhigher, a bandwidth larger than 24.25 kHz may be supported to overcomephase noise.

An NR frequency band may be defined by two types of frequency ranges,FR1 and FR2. FR1 and FR2 may be configured as described in Table 3below. FR2 may be millimeter wave (mmW).

TABLE 3 Frequency Range Corresponding frequency designation rangeSubcarrier Spacing FR1  450 MHz-7125 MHz 15, 30, 60 kHz FR2 24250MHz-52600 MHz 60, 120, 240 kHz

FIG. 3 illustrates a resource grid during the duration of one slot.

A slot includes a plurality of symbols in the time domain. For example,one slot includes 14 symbols in a normal CP case and 12 symbols in anextended CP case. A carrier includes a plurality of subcarriers in thefrequency domain. A resource block (RB) may be defined by a plurality of(e.g., 12) consecutive subcarriers in the frequency domain. A bandwidthpart (BWP) may be defined by a plurality of consecutive (physical) RBs((P)RBs) in the frequency domain and correspond to one numerology (e.g.,SCS, CP length, and so on). A carrier may include up to N (e.g., 5)BWPs. Data communication may be conducted in an active BWP, and only oneBWP may be activated for one UE. Each element in a resource grid may bereferred to as a resource element (RE), to which one complex symbol maybe mapped.

FIG. 4 illustrates exemplary mapping of physical channels in a slot.

A DL control channel, DL or UL data, and a UL control channel may all beincluded in one slot. For example, the first N symbols (hereinafter,referred to as a DL control region) in a slot may be used to transmit aDL control channel, and the last M symbols (hereinafter, referred to asa UL control region) in the slot may be used to transmit a UL controlchannel. N and M are integers equal to or greater than 0. A resourceregion (hereinafter, referred to as a data region) between the DLcontrol region and the UL control region may be used for DL datatransmission or UL data transmission. A time gap for DL-to-UL orUL-to-DL switching may be defined between a control region and the dataregion. A PDCCH may be transmitted in the DL control region, and a PDSCHmay be transmitted in the DL data region. Some symbols at the time ofswitching from DL to UL in a slot may be configured as the time gap.

Now, a detailed description will be given of physical channels.

The PDSCH delivers DL data (e.g., a downlink shared channel (DL-SCH)transport block (TB)) and adopts a modulation scheme such as quadraturephase shift keying (QPSK), 16-ary quadrature amplitude modulation (16QAM), 64-ary QAM (64 QAM), or 256-ary QAM (256 QAM). A TB is encoded toa codeword. The PDSCH may deliver up to two codewords. The codewords areindividually subjected to scrambling and modulation mapping, andmodulation symbols from each codeword are mapped to one or more layers.An OFDM signal is generated by mapping each layer together with a DMRSto resources, and transmitted through a corresponding antenna port.

The PDCCH delivers DCI. For example, the PDCCH (i.e., DCI) may carryinformation about a transport format and resource allocation of a DLshared channel (DL-SCH), resource allocation information of an uplinkshared channel (UL-SCH), paging information on a paging channel (PCH),system information on the DL-SCH, information on resource allocation ofa higher-layer control message such as an RAR transmitted on a PDSCH, atransmit power control command, information about activation/release ofconfigured scheduling, and so on. The DCI includes a cyclic redundancycheck (CRC). The CRC is masked with various identifiers (IDs) (e.g. aradio network temporary identifier (RNTI)) according to an owner orusage of the PDCCH. For example, if the PDCCH is for a specific UE, theCRC is masked by a UE ID (e.g., cell-RNTI (C-RNTI)). If the PDCCH is fora paging message, the CRC is masked by a paging-RNTI (P-RNTI). If thePDCCH is for system information (e.g., a system information block(SIB)), the CRC is masked by a system information RNTI (SI-RNTI). Whenthe PDCCH is for an RAR, the CRC is masked by a random access-RNTI(RA-RNTI).

The PDCCH uses a fixed modulation scheme (e.g., QPSK). One PDCCHincludes 1, 2, 4, 8, or 16 control channel elements (CCEs) according toits aggregation level (AL). One CCE includes 6 resource element groups(REGs), each REG being defined by one OFDM symbol by one (P)RB.

The PDCCH is transmitted in a control resource set (CORESET). TheCORESET corresponds to a set of physical resources/parameters used todeliver the PDCCH/DCI in a BWP. For example, the CORESET is defined as aset of REGs with a given numerology (e.g., an SCS, a CP length, or thelike). The CORESET may be configured by system information (e.g., amaster information block (MIB)) or UE-specific higher-layer signaling(e.g., RRC signaling). For example, the following parameters/informationmay be used to configure a CORESET, and a plurality of CORESETs mayoverlap with each other in the time/frequency domain.

-   -   controlResourceSetId: indicates the ID of a CORESET.    -   frequencyDomainResources: indicates the frequency area resources        of the CORESET. The frequency area resources are indicated by a        bitmap, and each bit of the bitmap corresponds to an RB group        (i.e., six consecutive RBs). For example, the most significant        bit (MSB) of the bitmap corresponds to the first RB group of a        BWP. An RB group corresponding to a bit set to 1 is allocated as        frequency area resources of the CORESET.    -   duration: indicates the time area resources of the CORESET. It        indicates the number of consecutive OFDMA symbols in the        CORESET. For example, the duration is set to one of 1 to 3.    -   cce-REG-MappingType: indicates a CCE-to-REG mapping type. An        interleaved type and a non-interleaved type are supported.    -   precoderGranularity: indicates a precoder granularity in the        frequency domain.    -   tci-StatesPDCCH: provides information indicating a transmission        configuration indication (TCI) state for the PDCCH (e.g.,        TCI-StateID). The TCI state is used to provide the        quasi-co-location relation between DL RS(s) in an RS set        (TCI-state) and PDCCH DMRS ports.    -   tci-PresentInDCI: indicates whether a TCI field is included in        DCI.    -   pdcch-DMRS-ScramblingID: provides information used for        initialization of a PDCCH DMRS scrambling sequence.

To receive the PDCCH, the UE may monitor (e.g., blind-decode) a set ofPDCCH candidates in the CORESET. The PDCCH candidates are CCE(s) thatthe UE monitors for PDCCH reception/detection. The PDCCH monitoring maybe performed in one or more CORESETs in an active DL BWP on each activecell configured with PDCCH monitoring. A set of PDCCH candidatesmonitored by the UE is defined as a PDCCH search space (SS) set. The SSset may be a common search space (CSS) set or a UE-specific search space(USS) set.

Table 4 lists exemplary PDCCH SSs.

TABLE 4 Search Type Space RNTI Use Case Type0- Common SI-RNTI on aprimary cell SIB Decoding PDCCH Type0A- Common SI-RNTI on a primary cellSIB Decoding PDCCH Type1- Common RA-RNTI or TC-RNTI Msg2, Msg4 PDCCH ona primary cell decoding in RACH Type2- Common P-RNTI Paging PDCCH on aprimary cell Decoding Type3- Common INT-RNTI, SFI-RNTI, TPC- PDCCHPUSCH-RNTI, TPC-PUCCH- RNTI, TPC-SRS-RNTI, C-RNTI, MCS-C-RNTI, orCS-RNTI(s) UE UE C-RNTI, or MCS-C-RNTI, User specific Specific Specificor CS-RNTI(s) PDSCH decoding

The SS set may be configured by system information (e.g., MIB) orUE-specific higher-layer (e.g., RRC) signaling. S or fewer SS sets maybe configured in each DL BWP of a serving cell. For example, thefollowing parameters/information may be provided for each SS set. EachSS set may be associated with one CORESET, and each CORESETconfiguration may be associated with one or more SS sets.

-   -   searchSpaceId: indicates the ID of the SS set.    -   controlResourceSetId: indicates a CORESET associated with the SS        set.    -   monitoringSlotPeriodicityAndOffset: indicates a PDCCH monitoring        periodicity (in slots) and a PDCCH monitoring offset (in slots).    -   monitoringSymbolsWithinSlot: indicates the first OFDMA symbol(s)        for PDCCH monitoring in a slot configured with PDCCH monitoring.        The OFDMA symbols are indicated by a bitmap and each bit of the        bitmap corresponds to one OFDM symbol in the slot. The MSB of        the bitmap corresponds to the first OFDM symbol of the slot.        OFDMA symbol(s) corresponding to bit(s) set to 1 corresponds to        the first symbol(s) of the CORESET in the slot.    -   nrofCandidates: indicates the number of PDCCH candidates (e.g.,        one of 0, 1, 2, 3, 4, 5, 6, and 8) for each AL={1, 2, 4, 8, 16}.    -   searchSpaceType: indicates whether the SS type is CSS or USS.    -   DCI format: indicates the DCI format of PDCCH candidates.

The UE may monitor PDCCH candidates in one or more SS sets in a slotbased on a CORESET/SS set configuration. An occasion (e.g.,time/frequency resources) in which the PDCCH candidates should bemonitored is defined as a PDCCH (monitoring) occasion. One or more PDCCH(monitoring) occasions may be configured in a slot.

Table 5 illustrates exemplary DCI formats transmitted on the PDCCH.

TABLE 5 DCI format Usage 0_0 Scheduling of PUSCH in one cell 0_1Scheduling of PUSCH in one cell 1_0 Scheduling of PDSCH in one cell 1_1Scheduling of PDSCH in one cell 2_0 Notifying a group of UEs of the slotformat 2_1 Notifying a group of UEs of the PRB(s) and OFDM symbol(s)where UE may assume no transmission is intended for the UE 2_2Transmission of TPC commands for PUCCH and PUSCH 2_3 Transmission of agroup of TPC commands for SRS transmissions by one or more UEs

DCI format 0_0 may be used to schedule a TB-based (or TB-level) PUSCH,and DCI format 0_1 may be used to schedule a TB-based (or TB-level)PUSCH or a code block group (CBG)-based (or CBG-level) PUSCH. DCI format1_0 may be used to schedule a TB-based (or TB-level) PDSCH, and DCIformat 1_1 may be used to schedule a TB-based (or TB-level) PDSCH or aCBG-based (or CBG-level) PDSCH (DL grant DCI). DCI format 0_0/0_1 may bereferred to as UL grant DCI or UL scheduling information, and DCI format1_0/1_1 may be referred to as DL grant DCI or DL scheduling information.DCI format 2_0 is used to deliver dynamic slot format information (e.g.,a dynamic slot format indicator (SFI)) to a UE, and DCI format 2_1 isused to deliver DL pre-emption information to a UE. DCI format 2_0and/or DCI format 2_1 may be delivered to a corresponding group of UEson a group common PDCCH which is a PDCCH directed to a group of UEs.

DCI format 0_0 and DCI format 1_0 may be referred to as fallback DCIformats, whereas DCI format 0_1 and DCI format 1_1 may be referred to asnon-fallback DCI formats. In the fallback DCI formats, a DCI size/fieldconfiguration is maintained to be the same irrespective of a UEconfiguration. In contrast, the DCI size/field configuration variesdepending on a UE configuration in the non-fallback DCI formats.

The PUCCH delivers uplink control information (UCI). The UCI includesthe following information.

-   -   SR: information used to request UL-SCH resources.    -   HARQ-ACK: a response to a DL data packet (e.g., codeword) on the        PDSCH. An HARQ-ACK indicates whether the DL data packet has been        successfully received. In response to a single codeword, a 1-bit        of HARQ-ACK may be transmitted. In response to two codewords, a        2-bit HARQ-ACK may be transmitted. The HARQ-ACK response        includes positive ACK (simply, ACK), negative ACK (NACK),        discontinuous transmission (DTX) or NACK/DTX. The term HARQ-ACK        is interchangeably used with HARQ ACK/NACK and ACK/NACK.    -   CSI: feedback information for a DL channel. Multiple input        multiple output (MIMO)-related feedback information includes an        RI and a PMI.

Table 6 illustrates exemplary PUCCH formats. PUCCH formats may bedivided into short PUCCHs (Formats 0 and 2) and long PUCCHs (Formats 1,3, and 4) based on PUCCH transmission durations.

TABLE 6 Length in PUCCH OFDM symbols Number of format N_(symb) ^(PUCCH)bits Usage Etc 0 1-2 <2 HARQ, SR Sequence selection 1  4-14 <2 HARQ,[SR] Sequence modulation 2 1-2 >2 HARQ, CSI, [SR] CP-OFDM 3  4-14 >2HARQ, CSI, [SR] DFT-s-OFDM (no UE multiplexing) 4  4-14 >2 HARQ, CSI,[SR] DFT-s-OFDM (Pre DFT OCC)

PUCCH format 0 conveys UCI of up to 2 bits and is mapped in asequence-based manner, for transmission. Specifically, the UE transmitsspecific UCI to the BS by transmitting one of a plurality of sequenceson a PUCCH of PUCCH format 0. Only when the UE transmits a positive SR,the UE transmits the PUCCH of PUCCH format 0 in PUCCH resources for acorresponding SR configuration.

PUCCH format 1 conveys UCI of up to 2 bits and modulation symbols of theUCI are spread with an orthogonal cover code (OCC) (which is configureddifferently whether frequency hopping is performed) in the time domain.The DMRS is transmitted in a symbol in which a modulation symbol is nottransmitted (i.e., transmitted in time division multiplexing (TDM)).

PUCCH format 2 conveys UCI of more than 2 bits and modulation symbols ofthe DCI are transmitted in frequency division multiplexing (FDM) withthe DMRS. The DMRS is located in symbols #1, #4, #7, and #10 of a givenRB with a density of ⅓. A pseudo noise (PN) sequence is used for a DMRSsequence. For 2-symbol PUCCH format 2, frequency hopping may beactivated.

PUCCH format 3 does not support UE multiplexing in the same PRBS, andconveys UCI of more than 2 bits. In other words, PUCCH resources ofPUCCH format 3 do not include an OCC. Modulation symbols are transmittedin TDM with the DMRS.

PUCCH format 4 supports multiplexing of up to 4 UEs in the same PRBS,and conveys UCI of more than 2 bits. In other words, PUCCH resources ofPUCCH format 3 include an OCC. Modulation symbols are transmitted in TDMwith the DMRS.

The PUSCH delivers UL data (e.g., UL-shared channel transport block(UL-SCH TB)) and/or UCI based on a CP-OFDM waveform or a DFT-s-OFDMwaveform. When the PUSCH is transmitted in the DFT-s-OFDM waveform, theUE transmits the PUSCH by transform precoding. For example, whentransform precoding is impossible (e.g., disabled), the UE may transmitthe PUSCH in the CP-OFDM waveform, while when transform precoding ispossible (e.g., enabled), the UE may transmit the PUSCH in the CP-OFDMor DFT-s-OFDM waveform. A PUSCH transmission may be dynamicallyscheduled by a UL grant in DCI, or semi-statically scheduled byhigher-layer (e.g., RRC) signaling (and/or Layer 1 (L1) signaling suchas a PDCCH) (configured scheduling or configured grant). The PUSCHtransmission may be performed in a codebook-based or non-codebook-basedmanner.

On DL, the BS may dynamically allocate resources for DL transmission tothe UE by PDCCH(s) (including DCI format 1_0 or DCI format 1_1).Further, the BS may indicate to a specific UE that some of resourcespre-scheduled for the UE have been pre-empted for signal transmission toanother UE, by PDCCH(s) (including DCI format 2_1). Further, the BS mayconfigure a DL assignment periodicity by higher-layer signaling andsignal activation/deactivation of a configured DL assignment by a PDCCHin a semi-persistent scheduling (SPS) scheme, to provide a DL assignmentfor an initial HARQ transmission to the UE. When a retransmission forthe initial HARQ transmission is required, the BS explicitly schedulesretransmission resources through a PDCCH. When a DCI-based DL assignmentcollides with an SPS-based DL assignment, the UE may give priority tothe DCI-based DL assignment.

Similarly to DL, for UL, the BS may dynamically allocate resources forUL transmission to the UE by PDCCH(s) (including DCI format 0_0 or DCIformat 0_1). Further, the BS may allocate UL resources for initial HARQtransmission to the UE based on a configured grant (CG) method(similarly to SPS). Although dynamic scheduling involves a PDCCH for aPUSCH transmission, a configured grant does not involve a PDCCH for aPUSCH transmission. However, UL resources for retransmission areexplicitly allocated by PDCCH(s). As such, an operation ofpreconfiguring UL resources without a dynamic grant (DG) (e.g., a ULgrant through scheduling DCI) by the BS is referred to as a “CG”. Twotypes are defined for the CG.

-   -   Type 1: a UL grant with a predetermined periodicity is provided        by higher-layer signaling (without L1 signaling).    -   Type 2: the periodicity of a UL grant is configured by        higher-layer signaling, and activation/deactivation of the CG is        signaled by a PDCCH, to provide the UL grant.

FIG. 5 illustrates exemplary UL transmission operations of a UE. The UEmay transmit an intended packet based on a DG (FIG. 5(a)) or based on aCG (FIG. 5(b)).

Resources for CGs may be shared between a plurality of UEs. A UL signaltransmission based on a CG from each UE may be identified bytime/frequency resources and an RS parameter (e.g., a different cyclicshift or the like). Therefore, when a UE fails in transmitting a ULsignal due to signal collision, the BS may identify the UE andexplicitly transmit a retransmission grant for a corresponding TB to theUE.

K repeated transmissions including an initial transmission are supportedfor the same TB by a CG. The same HARQ process ID is determined for Ktimes repeated UL signals based on resources for the initialtransmission. The redundancy versions (RVs) of a K times repeated TBhave one of the patterns {0, 2, 3, 1}, {0, 3, 0, 3}, and {0, 0, 0, 0}.

FIG. 6 illustrates exemplary repeated transmissions based on a CG.

The UE performs repeated transmissions until one of the followingconditions is satisfied:

-   -   A UL grant for the same TB is successfully received;    -   The repetition number of the TB reaches K; and    -   (In Option 2) the ending time of a period P is reached.

Similarly to licensed-assisted access (LAA) in the legacy 3GPP LTEsystem, use of an unlicensed band for cellular communication is alsounder consideration in a 3GPP NR system. Unlike LAA, a stand-along (SA)operation is aimed in an NR cell of an unlicensed band (hereinafter,referred to as NR unlicensed cell (UCell)). For example, PUCCH, PUSCH,and PRACH transmissions may be supported in the NR UCell.

In an NR system to which various embodiments of the present disclosureare applicable, up to 400 MHz per component carrier (CC) may beallocated/supported. When a UE operating in such a wideband CC alwaysoperates with a radio frequency (RF) module turned on for the entire CC,battery consumption of the UE may increase.

Alternatively, considering various use cases (e.g., eMBB, URLLC, mMTC,and so on) operating within a single wideband CC, a different numerology(e.g., SCS) may be supported for each frequency band within the CC.

Alternatively, each UE may have a different maximum bandwidthcapability.

In this regard, the BS may indicate to the UE to operate only in apartial bandwidth instead of the total bandwidth of the wideband CC. Thepartial bandwidth may be defined as a bandwidth part (BWP).

A BWP may be a subset of contiguous RBs on the frequency axis. One BWPmay correspond to one numerology (e.g., SCS, CP length, slot/mini-slotduration, and so on).

The BS may configure multiple BWPs in one CC configured for the UE. Forexample, the BS may configure a BWP occupying a relatively smallfrequency area in a PDCCH monitoring slot, and schedule a PDSCHindicated (or scheduled) by a PDCCH in a larger BWP. Alternatively, whenUEs are concentrated on a specific BWP, the BS may configure another BWPfor some of the UEs, for load balancing. Alternatively, the BS mayexclude some spectrum of the total bandwidth and configure both-sideBWPs of the cell in the same slot in consideration of frequency-domaininter-cell interference cancellation between neighboring cells.

The BS may configure at least one DL/UL BWP for a UE associated with thewideband CC, activate at least one of DL/UL BWP(s) configured at aspecific time point (by L1 signaling (e.g., DCI), MAC signaling, or RRCsignaling), and indicate switching to another configured DL/UL BWP (byL1 signaling, MAC signaling, or RRC signaling). Further, upon expirationof a timer value (e.g., a BWP inactivity timer value), the UE may switchto a predetermined DL/UL BWP. The activated DL/UL BWP may be referred toas an active DL/UL BWP. During initial access or before an RRCconnection setup, the UE may not receive a configuration for a DL/UL BWPfrom the BS. A DL/UL BWP that the UE assumes in this situation isdefined as an initial active DL/UL BWP.

EMBODIMENTS OF THE PRESENT DISCLOSURE

FIG. 7 illustrates an exemplary wireless communication system supportingan unlicensed band applicable to the present disclosure.

In the following description, a cell operating in a licensed band(L-band) is defined as an L-cell, and a carrier of the L-cell is definedas a (DL/UL) LCC. A cell operating in an unlicensed band (U-band) isdefined as a U-cell, and a carrier of the U-cell is defined as a (DL/UL)UCC. The carrier/carrier-frequency of a cell may refer to the operatingfrequency (e.g., center frequency) of the cell. A cell/carrier (e.g.,CC) is commonly called a cell.

When a BS and a UE transmit and receive signals on carrier-aggregatedLCC and UCC as illustrated in FIG. 7(a), the LCC and the UCC may beconfigured as a primary CC (PCC) and a secondary CC (SCC), respectively.The BS and the UE may transmit and receive signals on one UCC or on aplurality of carrier-aggregated UCCs as illustrated in FIG. 7(b). Inother words, the BS and UE may transmit and receive signals only onUCC(s) without using any LCC. For an SA operation, PRACH, PUCCH, PUSCH,and SRS transmissions may be supported on a UCell.

Signal transmission and reception operations in an unlicensed band asdescribed in the present disclosure may be applied to theafore-mentioned deployment scenarios (unless specified otherwise).

Unless otherwise noted, the definitions below are applicable to thefollowing terminologies used in the present disclosure.

-   -   Channel: a carrier or a part of a carrier composed of a        contiguous set of RBs in which a channel access procedure (CAP)        is performed in a shared spectrum.    -   Channel access procedure (CAP): a procedure of assessing channel        availability based on sensing before signal transmission in        order to determine whether other communication node(s) are using        a channel. A basic sensing unit is a sensing slot with a        duration of Tsl=9 μs. The BS or the UE senses the slot during a        sensing slot duration. When power detected for at least 4 μs        within the sensing slot duration is less than an energy        detection threshold XThresh, the sensing slot duration Tsl is be        considered to be idle. Otherwise, the sensing slot duration Tsl        is considered to be busy. CAP may also be called listen before        talk (LBT).    -   Channel occupancy: transmission(s) on channel(s) from the BS/UE        after a CAP.    -   Channel occupancy time (COT): a total time during which the        BS/UE and any BS/UE(s) sharing channel occupancy performs        transmission(s) on a channel after a CAP. Regarding COT        determination, if a transmission gap is less than or equal to 25        μs, the gap duration may be counted in a COT. The COT may be        shared for transmission between the BS and corresponding UE(s).    -   DL transmission burst: a set of transmissions without any gap        greater than 16 μs from the BS. Transmissions from the BS, which        are separated by a gap exceeding 16 μs are considered as        separate DL transmission bursts. The BS may perform        transmission(s) after a gap without sensing channel availability        within a DL transmission burst.    -   UL transmission burst: a set of transmissions without any gap        greater than 16 μs from the UE. Transmissions from the UE, which        are separated by a gap exceeding 16 μs are considered as        separate UL transmission bursts. The UE may perform        transmission(s) after a gap without sensing channel availability        within a DL transmission burst.    -   Discovery burst: a DL transmission burst including a set of        signal(s) and/or channel(s) confined within a window and        associated with a duty cycle. The discovery burst may include        transmission(s) initiated by the BS, which includes a PSS, an        SSS, and a cell-specific RS (CRS) and further includes a        non-zero power CSI-RS. In the NR system, the discover burst        includes may include transmission(s) initiated by the BS, which        includes at least an SS/PBCH block and further includes a        CORESET for a PDCCH scheduling a PDSCH carrying SIB1, the PDSCH        carrying SIB1, and/or a non-zero power CSI-RS.

FIG. 8 illustrates an exemplary method of occupying resources in anunlicensed band.

Referring to FIG. 8 , a communication node (e.g., a BS or a UE)operating in an unlicensed band should determine whether othercommunication node(s) is using a channel, before signal transmission.For this purpose, the communication node may perform a CAP to accesschannel(s) on which transmission(s) is to be performed in the unlicensedband. The CAP may be performed based on sensing. For example, thecommunication node may determine whether other communication node(s) istransmitting a signal on the channel(s) by carrier sensing (CS) beforesignal transmission. Determining that other communication node(s) is nottransmitting a signal is defined as confirmation of clear channelassessment (CCA). In the presence of a CCA threshold (e.g., Xthresh)which has been predefined or configured by higher-layer (e.g., RRC)signaling, the communication node may determine that the channel isbusy, when detecting energy higher than the CCA threshold in thechannel. Otherwise, the communication node may determine that thechannel is idle. When determining that the channel is idle, thecommunication node may start to transmit a signal in the unlicensedband. CAP may be replaced with LBT.

Table 7 describes an exemplary CAP supported in NR-U.

TABLE 7 Type Explanation DL Type 1 CAP with random backoff CAP timeduration spanned by the sensing slots that are sensed to be idle beforea downlink transmission(s) is random Type 2 CAP without random backoffCAP time duration spanned by sensing slots that are Type 2A, sensed tobe idle before a downlink transmission(s) 2B, 2C is deterministic ULType 1 CAP with random backoff CAP time duration spanned by the sensingslots that are sensed to be idle before a downlink transmission(s) israndom Type 2 CAP without random backoff CAP time duration spanned bysensing slots that are Type 2A, sensed to be idle before a downlinktransmission(s) 2B, 2C is deterministic

In a wireless communication system supporting an unlicensed band, onecell (or carrier (e.g., CC)) or BWP configured for a UE may be awideband having a larger bandwidth (BW) than in legacy LTE. However, aBW requiring CCA based on an independent LBT operation may be limitedaccording to regulations. Let a subband (SB) in which LBT isindividually performed be defined as an LBT-SB. Then, a plurality ofLBT-SBs may be included in one wideband cell/BWP. A set of RBs includedin an LBT-SB may be configured by higher-layer (e.g., RRC) signaling.Accordingly, one or more LBT-SBs may be included in one cell/BWP basedon (i) the BW of the cell/BWP and (ii) RB set allocation information.

A plurality of LBT-SBs may be included in the BWP of a cell (orcarrier). An LBT-SB may be, for example, a 20-MHz band. The LBT-SB mayinclude a plurality of contiguous (P)RBs in the frequency domain, andthus may be referred to as a (P)RB set.

A UE performs a Type 1 or Type 2 CAP for a UL signal transmission in anunlicensed band. In general, the UE may perform a CAP (e.g., Type 1 orType 2) configured by a BS, for a UL signal transmission. For example,CAP type indication information may be included in a UL grant (e.g., DCIformat 0_0 or DCI format 0_1) that schedules a PUSCH transmission.

In the Type 1 UL CAP, the length of a time period spanned by sensingslots sensed as idle before transmission(s) is random. The Type 1 UL CAPmay be applied to the following transmissions.

-   -   PUSCH/SRS transmission(s) scheduled and/or configured by BS    -   PUCCH transmission(s) scheduled and/or configured by BS    -   Transmission(s) related to random access procedure (RAP)

FIG. 9 illustrates a Type 1 CAP among CAPs of a UE for a UL signaltransmission in an unlicensed band applicable to the present disclosure.

Referring to FIG. 9 , the UE may sense whether a channel is idle for asensing slot duration in a defer duration Td. After a counter N isdecremented to 0, the UE may perform a transmission (S934). The counterN is adjusted by sensing the channel for additional slot duration(s)according to the following procedure.

Step 1) Set N=Ninit where Ninit is a random number uniformly distributedbetween 0 and CWp, and go to step 4 (S920).

Step 2) If N>0 and the UE chooses to decrement the counter, set N=N−1(S940).

Step 3) Sense the channel for an additional slot duration, and if theadditional slot duration is idle (Y), go to step 4. Else (N), go to step5 (S950).

Step 4) If N=0 (Y) (S930), stop CAP (S932). Else (N), go to step 2.

Step 5) Sense the channel until a busy sensing slot is detected withinthe additional defer duration Td or all slots of the additional deferduration Td are sensed as idle (S960).

Step 6) If the channel is sensed as idle for all slot durations of theadditional defer duration Td (Y), go to step 4. Else (N), go to step 5(S970).

Table 8 illustrates that mp, a minimum CW, a maximum CW, a maximumchannel occupancy time (MCOT), and an allowed CW size applied to a CAPvary according to channel access priority classes.

TABLE 8 Channel Access Priority Class (p) m_(p) CW_(min,p) CW_(max,p)T_(ulmcot,p) allowed CW_(p) sizes 1 2 3 7 2 ms {3, 7} 2 2 7 15 4 ms {7,15} 3 3 15 1023 6 or 10 ms {15, 31, 63, 127, 255, 511, 1023} 4 7 15 10236 or 10 ms {15, 31, 63, 127, 255, 511, 1023}

The defer duration T_(d) includes a duration T_(f) (16 μs) immediatelyfollowed by m_(p) consecutive slot durations where each slot durationT_(sl) is 9 μs, and T_(f) includes a sensing slot duration T_(sl) at thestart of the 16-μs duration.

CW_(min,p)<=CW_(p)<=CW_(max,p). CW_(p) is set to CW_(min,p), and may beupdated before Step 1 based on an explicit/implicit reception responseto a previous UL burst (e.g., PUSCH) (CW size update). For example,CW_(p) may be initialized to CW_(min,p) based on an explicit/implicitreception response to the previous UL burst, may be increased to thenext higher allowed value, or may be maintained to be an existing value.

In the Type 2 UL CAP, the length of a time period spanned by sensingslots sensed as idle before transmission(s) is deterministic. Type 2 ULCAPs are classified into Type 2A UL CAP, Type 2B UL CAP, and Type 2C ULCAP. In the Type 2A UL CAP, the UE may transmit a signal immediatelyafter the channel is sensed as idle during at least a sensing durationT_(short_dl) (=25 μs). T_(short_dl) includes a duration T_(f) (=16 μs)and one immediately following sensing slot duration. In the Type 2A ULCAP, T_(f) includes a sensing slot at the start of the duration. In theType 2B UL CAP, the UE may transmit a signal immediately after thechannel is sensed as idle during a sensing slot duration T_(f) (=16 μs).In the Type 2B UL CAP, T_(f) includes a sensing slot within the last 9μs of the duration. In the Type 2C UL CAP, the UE does not sense achannel before a transmission.

The present disclosure proposes a method of indicating an LBT type and aPUSCH starting position, for UL transmission scheduling, and a method ofperforming UL transmission based on the indicated LBT type and PUSCHstarting position, in a wireless communication system including a BS anda UE in an unlicensed band. The present disclosure also proposes amethod of configuring a reference resource, which is referred to when acontention window size (CWS) is adjusted, by receiving a result of aPDSCH or PUSCH transmission through feedback.

To allow the UE to transmit UL data in the unlicensed band, the BSshould succeed in an LBT operation to transmit a UL grant in theunlicensed band, and the UE should also succeed in an LBT operation totransmit the UL data. That is, only when both of the BS and the UEsucceed in their LBT operations, the UE may attempt the UL datatransmission. Further, because a delay of at least 4 msec is involvedbetween a UL grant and scheduled UL data in the LTE system, earlieraccess from another transmission node coexisting in the unlicensed bandduring the time period may defer the scheduled UL data transmission ofthe UE. In this context, a method of increasing the efficiency of ULdata transmission in an unlicensed band is under discussion.

In LTE LAA, the BS may inform the UE of an autonomous uplink (AUL)subframe or slot for autonomous UL transmission, in which the UE maytransmit UL data without receiving a UL grant, through an X-bit bitmap(e.g., X=40 bits).

When autonomous transmission activation is indicated to the UE, the UEmay transmit UL data in a subframe or slot indicated through a relatedbitmap even without receiving the UL grant. Upon transmitting a PDSCH tothe UE, the BS also transmits a PDCCH, which is scheduling informationrequired for decoding. Likewise, upon transmitting a PUSCH on AUL to theBS, the UE also transmits AUL UCI, which is information required whenthe BS decodes the PUSCH. The AUL UCI includes information needed toreceive an AUL PUSCH, such as a HARQ ID, a new data indicator (NDI), aredundancy version (RV), an AUL subframe starting position, and an AULsubframe ending position, and information for sharing a UE-initiated COTwith the BS. “Sharing a UE-initiated COT with the BS” means an operationof assigning a part of a channel occupied by the UE through randombackoff-based category 4 LBT (or Type 1 CAP) to the BS and transmittinga PDCCH (and a PDSCH) on the channel by the BS, when the channel is idleas a result of one-shot LBT of 25 μsec (based on a timing gap resultingfrom the UE's emptying of the last symbol).

To support a UL transmission having a relatively high reliability and arelatively low time delay, NR also supports CG type 1 and CG type 2 inwhich the BS preconfigures time, frequency, and code resources for theUE by higher-layer signaling (e.g., RRC signaling) or both ofhigher-layer signaling and L1 signaling (e.g., DCI). Without receiving aUL grant from the BS, the UE may perform a UL transmission in resourcesconfigured with type 1 or type 2. In type 1, the periodicity of a CG, anoffset from SFN=0, time/frequency resource allocation, a repetitionnumber, a DMRS parameter, an MCS/TB size (TBS), a power controlparameter, and so on are all configured only by higher-layer signalingsuch as RRC signaling, without L1 signaling. Type 2 is a scheme ofconfiguring the periodicity of a CG and a power control parameter byhigher-layer signaling such as RRC signaling and indicating informationabout the remaining resources (e.g., the offset of an initialtransmission timing, time/frequency resource allocation, a DMRSparameter, and an MCS/TBS) by activation DCI as L1 signaling.

AUL of LTE LAA and a CG of NR show a big difference in terms of a methodof transmitting HARQ-ACK feedback for a PUSCH that the UE hastransmitted without receiving a UL grant and in terms of the presence orabsence of UCI transmitted along with the PUSCH. While a HARQ process isdetermined by an equation of a symbol index, a symbol periodicity, andthe number of HARQ processes in the CG of NR, explicit HARQ-ACK feedbackinformation is transmitted in AUL downlink feedback information(AUL-DFI) in LTE LAA. Further, in LTE LAA, UCI including informationsuch as a HARQ ID, an NDI, and an RV is also transmitted in AUL UCIwhenever AUL PUSCH transmission is performed. In the case of the CG ofNR, the BS identifies the UE by time/frequency resources and DMRSresources used for PUSCH transmission, whereas in the case of LTE LAA,the BS identifies the UE by a UE ID explicitly included in the AUL UCItransmitted together with the PUSCH as well as the DMRS resources.

Before a description of proposed methods, NR-based channel accessschemes for an unlicensed band used in the present disclosure areclassified as follows.

-   -   Category 1 (Cat-1): the next transmission immediately follows        the previous transmission after a switching gap within a COT,        and the switching gap is shorter than 16 μs, including even a        transceiver turn-around time. Cat-1 LBT may correspond to the        above-described Type 2C CAP.    -   Category 2 (Cat-2): an LBT method without backoff. Once a        channel is confirmed to be idle during a specific time period        shortly before transmission, the transmission may be performed        immediately. Cat-2 LBT may be subdivided according to the length        of a minimum sensing duration required for channel sensing        immediately before a transmission. For example, Cat-2 LBT with a        minimum sensing duration of 25 μs may correspond to the        above-described Type 2A CAP, and Cat-2 LBT with a minimum        sensing duration of 16 μs may correspond to the above-described        Type 2B CAP. The minimum sensing durations are merely exemplary,        and a minimum sensing duration less than 25 μs or 16 μs (e.g., a        minimum sensing duration of 9 μs) may also be available.    -   Category 3 (Cat-3): an LBT method with fixed contention window        size (CWS)i-based backoff. A transmitting entity selects a        random number N in a range of 0 to a (fixed) maximum CWS value        and decrements a counter value each time it determines that a        channel is idle. When the counter value reaches 0, the        transmitting entity is allowed to perform a transmission.    -   Category 4 (Cat-4): an LBT method with variable CWS-based        backoff. A transmitting entity selects a random number N in a        range of 0 to a (variable) maximum CWS value and decrements a        counter value, each time it determines that a channel is idle.        When the counter value reaches 0, the transmitting entity is        allowed to perform a transmission. If the transmitting entity        receives a feedback indicating reception failure of the        transmission, the transmitting entity increases the maximum CWS        value by one level, selects a random number again within the        increased CWS value, and performs an LBT procedure. Cat-4 LBT        may correspond to the above-described Type 1 CAP.

The following description is given with the appreciation that the termband may be interchangeably used with CC/cell, and a CC/cell (index) maybe replaced with a BWP (index) configured within the CC/cell, or acombination of the CC/cell (index) and the BWP (index).

Terms are defined as follows.

-   -   UCI: control information transmitted on UL by the UE. UCI        includes various types of control information (i.e., UCI types).        For example, the UCI may include an HARQ-ACK (simply, A/N or        AN), an SR, and CSI.    -   PUCCH: a physical layer UL channel for UCI transmission. For        convenience, PUCCH resources configured and/or indicated for        A/N, SR, and CSI transmission are referred to as A/N PUCCH        resources, SR PUCCH resources, and CSI PUCCH resources,        respectively.    -   UL grant DCI: DCI for a UL grant. For example, UL grant DCI        means DCI formats 0_0 and 0_1, and is transmitted on a PDCCH.    -   DL assignment/grant DCI: DCI for a DL grant. For example, DL        assignment/grant DCI means DCI formats 1_0 and 1_1, and is        transmitted on a PDCCH.    -   PUSCH: a physical layer UL channel for UL data transmission.    -   Slot: a basic time unit (TU) (or time interval) for data        scheduling. A slot includes a plurality of symbols. Herein, a        symbol includes an OFDM symbol (e.g., CP-OFDM symbol or        DFT-s-OFDM symbol). In this specification, the terms symbol,        OFDM-based symbol, OFDM symbol, CP-OFDM symbol, and DFT-s-OFDM        symbol may be replaced with each other.    -   Performing LBT for channel X/with respect to channel X: This        means that performing LBT in order to confirm whether to        transmit channel X. For example, a CAP may be performed before        transmission of channel X is started.

In LTE enhanced LAA (eLAA), two types of CAPs for UL data transmissionhave been broadly defined. CAP Type 1 (hereinafter, Cat-4 LBT) is abackoff-based mechanism similar to a CAP used for DL data transmission,whereas CAP type 2 (hereinafter, 25 μs Cat-2 LBT) is a mechanism ofstarting UL transmission by regarding a channel to be idle when energymeasured through short CCA of a minimum of 25 us or more immediatelybefore UL transmission is lower than a threshold. According to adescription of ETSI EN 301 893, the UE (or a responding device) mayperform UL transmission without CCA if the UE performs UL transmissionbefore 16 μs after receiving a UL grant from the BS (or an initiatingdevice). The present disclosure refers to a procedure of performing ULtransmission without LBT because a gap between DL transmission and ULtransmission is less than 16 μs as Cat-1 LBT, and a procedure ofstarting UL transmission by regarding a channel to be idle if energymeasured through short CCA of 16 us immediately before transmission islower than a threshold as 16 μs Cat-2 LBT.

Transmission of UL data such as a PUSCH is indicated through DCI (i.e.,a UL grant) transmitted through a PDCCH|. The DCI includes informationabout an LBT type and a PUSCH starting position which will be used bythe UE during a CAP. Specifically, in legacy LTE eLAA, whether a CAPtype to be used for the CAP is Type 1 (Cat-4 LBT) or type 2 (25 μs Cat-2LBT) is indicated through a 1-bit field in the UL grant DCI, and one of4 PUSCH starting positions {symbol #0, symbol #0+25 μs, symbol #0+25μs+timing advance (TA), symbol #1} is indicated through another 2-bitfield.

In NR, the BS may indicate, to the UE, a time domain resource of aPUSCH, i.e., the position of a starting symbol of the PUSCH and thenumber of symbols constituting the PUSCH, through a start and lengthindicator value (SLIV) in the UL grant. In other words, all symbolsconstituting a slot are not always used for PUSCH transmission, and thePUSCH corresponding to a length from the starting symbol indicatedthrough the SLIV is transmitted. Therefore, the PUSCH starting positionhas conventionally been present between symbol #0 and symbol #1, whereasin NR, the PUSCH starting position may be present between symbol #K andsymbol #(K-N) according to an SCS and a gap between transmissions, basedon a starting symbol symbol #K indicated through the SLIV.

When a symbol indicated through the SLIV is symbol #K, candidates of anavailable PUSCH starting position may be defined as {symbol #(K-N)+16μs, symbol #(K-N)+16 μs+TA, symbol #(K-N)+25 μs, symbol #(K-N)+25 μs+TA,symbol #K}, and {symbol #(K-N)+16 μs+TA} may be replaced with {symbol#(K−1)+max(16 μs, TA)}. If there is TA in the first symbol of the nextslot after DL transmission is performed up to a symbol immediatelybefore a PUSCH transmission starting symbol (e.g., when UL transmissionstarts immediately after (16 μs-TA) after DL reception), {symbol#(K−1)+16 μs+TA} may be excluded from the candidates of the PUSCHstarting position. N may be predefined as a specific value (e.g., N=1)or may be separately configured/indicated through RRC signaling (or DCIor a combination of RRC and DCI). Alternatively, the N value may be(scalably) configured by the BS for the UE as a different valueaccording to numerology. For example, N=1 for 15 kHz and N=2 for 30 kHz,according to an SCS.

For BS-initiated (or gNB-initiated) channel occupancy, a referenceduration for CWS adjustment may be defined as follows. For channeloccupancy with unicast PDSCH and a set of LBT bandwidths in which asingle contention window is maintained, the reference duration for CWSadjustment may be the first generated duration among a duration from thestart of channel occupancy to the end of the first slot in which atleast one unicast PDSCH is transmitted through all resources allocatedto a PDSCH and a duration from the start of channel occupancy to the endof the first transmission burst including unicast PDSCH(s) transmittedby the BS through all resources allocated to the PDSCH.

If there is channel occupancy with the unicast PDSCH but the unicastPDSCH is not transmitted through all resources allocated to the PDSCH, aduration of the first transmission burst by the BS in channel occupationincluding the unicast PDSCH may be the reference duration for CWSadjustment.

For UE-initiated channel occupancy, the reference duration for CWSadjustment may be defined as follows. For channel occupancy with a PUSCHand a set of LBT bandwidths in which a single contention window ismaintained, the reference duration for CWS adjustment may be the firstgenerated duration among a duration from the start of channel occupancyto the end of the first slot in which at least one PUSCH is transmittedthrough all resources allocated to the PUSCH and a duration from thestart of channel occupancy to the end of the first transmission burstincluding PUSCH(s) transmitted by the UE through all resources allocatedto the PUSCH. If there is channel occupation with the PUSCH but thePUSCH is not transmitted through all resources allocated to the PUSCH,the duration of the first transmission burst by the UE in channeloccupation including PUSCH(s) may be the reference duration for CWSadjustment.

Prior to a description of proposed methods, frame-based equipment (FBE)and load-based equipment (LBE) in this disclosure will be brieflydescribed. The FBE refers to a device that transmits and receivessignals based on a periodic time such as a frame fixed period (FFP), andthe LBE refers a device that transmits and receives signals uponintending to transmit/receive signals regardless of a period. An FBEmode and an LBE mode may be types of channel access modes. A wirelesscommunication system of an unlicensed band to which the presentdisclosure is applied may support both the FBE mode and the LBE mode asthe channel access mode. When the BS or the UE operates in the FBE mode,the BS and the UE may transmit signals in the next FFP by performing aCAP in an idle period within the FFP. In contrast, when the BS or the UEoperates in the LBE mode, the BS and the UE may transmit signals byperforming the CAP upon intending to transmit signals regardless of aspecific period. In the LBE mode, both a random backoff-based CAP (e.g.,Type 1 CAP or Cat-4 LBT) and non-random backoff CAP may be performed. Inthe FBE mode, the random backoff-based CAP is not performed.

In addition, CP insertion is used in OFDM transmission. CP insertionmeans that the last part of an OFDM symbol is copied and inserted intothe beginning of the OFDM symbol. Transmission after filling a CP infront of a specific OFDM symbol by adjusting a CP length may be referredto as CP extension (CPE), and CPE of an appropriate length is requiredaccording to an LBT type and an SCS.

[Proposed Method #1] Method of transmitting UL data by receiving, fromthe BS, a PUSCH transmission starting symbol, symbol #K, indicatedthrough an SLIV in a UL grant and receiving an LBT type of a PUSCH and aPUSCH starting position indicated as follows

(1-1) Method of receiving one of states combined by 4 LBT types and 5PUSCH starting positions, indicated through a specific 4-bit field inthe UL grant

Table 9 below shows an LBT type and a PUSCH starting position configuredby joint encoding.

TABLE 9 State LBT type PUSCH starting position 0 Cat-1 LBT Symbol #(K-N) + 16 μs 1 Cat-1 LBT Symbol # (K-N) + 16 μs + TA 2 Cat-1 LBT Symbol# (K) 3 16 μs Cat-2 LBT Symbol # (K-N) + 16 μs 4 16 μs Cat-2 LBT Symbol# (K-N) + 16 μs + TA 5 16 μs Cat-2 LBT Symbol # (K) 6 25 μs Cat-2 LBTSymbol # (K-N) + 25 μs 7 25 μs Cat-2 LBT Symbol # (K-N) + 25 μs + TA 825 μs Cat-2 LBT Symbol # (K) 9 Cat-4 LBT Symbol # (K-N) + 16 μs 10 Cat-4LBT Symbol # (K-N) + 16 μs + TA 11 Cat-4 LBT Symbol # (K-N) + 25 μs 12Cat-4 LBT Symbol # (K-N) + 25 μs + TA 13 Cat-4 LBT Symbol # (K) 14Reserved 15 Reserved

In Table 9, one or both of states in which the LBT type is Cat-1 LBT or16 μs Cat-2 LBT and the PUSCH starting position is symbol #(K), i.e.,one or both of state #2 and state #5, may be excluded from statesrequiring an indication. In addition, state #1 may also be excluded.This is because, in Cat-1 LBT, the UE may perform UL transmissionwithout channel sensing as long as a gap between transmissions is 16 μsor less and, in 16 μs Cat-2 LBT, LBT may be performed only when an exact16 μs gap should be guaranteed. In Table 9, N is a value that isdifferently predefined (in the standard) for each state or isconfigured/indicated by the BS. When the PUSCH starting position isindicated, only a gap for LBT (e.g., only 16 μs in the case of state#0), except for symbol #(K-N) in Table 9, may be signaled.

(1-2) Method of distinguishing between [Cat-1 LBT, Cat-2 LBT] and [Cat-4LBT] through a 1-bit flag in the UL grant and receiving one of statescombined by the LBT types and the PUSCH starting positions, indicatedthrough another 3-bit field

Table 10 below shows exemplary combinations of the LBT types and thePUSCH starting positions when [Cat-1 LBT, Cat-2 LBT] is indicated.

TABLE 10 State LBT type PUSCH starting position 0 Cat-1 LBT Symbol #(K-N) + 16 μs 1 Cat-1 LBT Symbol # (K-N) + 16 μs + TA 2 Cat-1 LBT Symbol# K 3 16 μs Cat-2 LBT Symbol # (K-N) + 16 μs 4 16 μs Cat-2 LBT Symbol #(K-N) + 16 μs + TA 5 25 μs Cat-2 LBT Symbol # (K-N) + 25 μs 6 25 μsCat-2 LBT Symbol # (K-N) + 25 μs + TA 7 25 μs Cat-2 LBT Symbol # K

Table 11 below shows an example of combinations of the LBT types and thePUSCH starting position when [Cat-4 LBT] is indicated.

TABLE 11 State LBT type PUSCH starting position 0 Cat-4 LBT Symbol #(K-N) + 16 μs 1 Cat-4 LBT Symbol # (K-N) + 16 μs + TA 2 Cat-4 LBT Symbol# (K-N) + 25 μs 3 Cat-4 LBT Symbol # (K-N) + 25 μs + TA 4 Cat-4 LBTSymbol # K 5 Reserved 6 Reserved 7 Reserved

In Table 10, one or both of states in which the LBT type is Cat-1 LBT or16 μs Cat-2 LBT and the PUSCH starting position is symbol #(K), i.e.,one or both of state #1 and state #2 in Table 10, may be excluded fromstates requiring an indication. This is because, in Cat-1 LBT, the UEmay perform UL transmission without channel sensing as long as a gapbetween transmissions is 16 μs or less and, in 16 μs Cat-2 LBT, LBT maybe performed only when an exact 16 μs gap should be guaranteed. In thetables, N is a value that is differently predefined (in the standard)for each state or is configured/indicated by the BS. When the PUSCHstarting position is indicated, only a gap for LBT (e.g., only 16 μs inthe case of state #0), except for symbol #(K-N) in the above table, maybe signaled.

If 4 LBT types and 5 PUSCH starting positions are indicated throughrespective individual fields in the UL grant, a total of 5 bits isrequired. However, a cell configured to use only some of the 4 LBT typesthrough a higher layer signal such as RRC signaling or through remainingminimum system information (RMSI) may need not indicate all LBT typesand PUSCH starting positions. For example, a cell operating in the FBEmode needs to indicate only one of the remaining two LBT types exceptfor Cat-4 LBT and 16 μs Cat-2 LBT to the UE. As another example, whenthe use of the remaining 3 LBT types except for 25 μs Cat-2 LBT amongthe 4 LBT types is semi-statically indicated through RRC signaling, andone of the 3 LBT types is dynamically indicated through the UL grant, ifthe PUSCH transmission starting symbol is indicated as symbol #K throughthe SLIV, {symbol #(K-N)+25 μs, symbol #(K-N)+25 μs+TA} among the PUSCHstarting positions may not need to be indicated.

As in (1-1), the BS may define one state by combining one LBT type andone PUSCH starting position to configure states through the RMSI or RRCsignaling or the states may be predefined in the standard. Table 9 is anexample of defining the LBT type and the PUSCH starting position as onestate, and the order of states constituting an actual table or thenumber of the states may be different from those shown in Table 9. Asmentioned in the description above, all combinations may be composed asstates as shown in Table 9 and may be configured and defined. Then, onlysome states to be actually used may be configured/indicated. That is,only some states from a set of the combinations of the total LBT typesand PUSCH starting positions may be configured for/indicated to the UEas a subset according to an operating mode or specific purpose of acell.

Another method of indicating the LBT type and PUSCH starting position isto distinguish between [Cat-1 LBT, Cat-2 LBT] and [Cat-4] (i.e., dividethe LBT type into Cat-4 LBT and non-Cat-4 LBT) through a 1-bit flag inthe UL grant and to indicate one state in which the LBT type and thePUSCH starting position are combined through another 3-bit field, as in(1-2). Table 10 shows an example configured by combining Cat-1 or Cat-2LBT and a PUSCH starting position corresponding thereto when the 1-bitflag indicates [Cat-1 LBT, Cat-2 LBT]. Table 11 shows configurable PUSCHstating positions when [Cat-4 LBT] is indicated. The advantage of thismethod is that, when a specific cell operates in the FBE mode, the 1-bitflag and Table 11 may not be used because Cat-4 LBT need not beindicated.

Tables 10 and 11 are examples shown by defining the LBT type and thePUSCH starting position as one state, and the order of statesconstituting an actual table or the number of the states may bedifferent from those shown in Tables 10 and 11. In addition, only somestates from the set of the combinations of the total LBT types and PUSCHstarting positions that may be indicated when the LBT type is [Cat-1,Cat-2 LBT] or [Cat-4 LBT] may be configured/indicated as a subsetaccording to an operating mode or specific purpose of the cell.

[Proposed Method #2] Method of configuring a field indicating an LBTtype and a PUSCH starting position (or a state of combining the two) ina UL grant (or DL assignment), when the BS configures, for the UE,information about an LBT type or a channel access mode (e.g., FBE modeor LBE mode) to be used in a corresponding cell through a higher layersignal such as RRC or the BS informs the UE of the information through aphysical layer signal such as DCI or through a combination of the higherlayer signal and the physical layer signal

Four LBT types that the BS may indicate to the UE are {Cat-1 LBT, 16 μsCat-2 LBT, 25 μs Cat-2 LBT, Cat-4 LBT}. However, according to thecapability of the UE or the operation mode of the cell, the UE may beindicated to use only some of the 4 LBT types. Two bits are needed toindicate a total of 4 LBT types. However, when only some LBT types areconfigured/indicated to be used, since only one of theconfigured/indicated LBT types needs to be indicated, the number of bitsneeded to indicate an LBT type in the UL grant (or DL allocation forPUCCH transmission) may be less than two bits. For example, if the UEreports on non-support of Cat-1 LBT and 16 μs Cat-2 LBT, the BS onlyneeds to indicate one of 25 μs Cat-2 LBT and Cat-4 LBT through one bit.If the UE is informed through a higher layer signal (e.g., SIB) that thecell is operating in the FBE mode, the UE may expect that one of theremaining 3 LBT types except for Cat-4 LBT among the 4 LBT types will beindicated. Alternatively, the BS may inform the UE in advance of an LBTtype to be used through a higher layer signal, a physical layer signal,or a combination thereof and may indicate one of the 3 LBT types.

If the LBT type to be indicated to the UE is configured/indicated inadvance as described above, a PUSCH starting position candidate setindicated together with the LBT type may also vary accordingly. When thePUSCH starting position, symbol #K, is indicated to the UE through theSLIV, the candidate sets of PUSCH starting positions that may beindicated are four in total, i.e., {symbol #(K-C1)+25 μs, symbol#(K-C2)+16 μs+TA, symbol #(K-C3)+25 μs+TA, symbol #K}. However, sincethe PUSCH starting position corresponds to each LBT type, a PUSCHstarting position subset may be determined according to the LBT typeconfigured for/indicated to the corresponding cell. Here, C1, C2, and C3values may be different according to an SCS and a PUSCH startingposition candidate, and a gap from a corresponding starting position tosymbol #K may be filled through CPE of the first symbol of the PUSCH.For example, if the LBT type configured for/indicated to the cell isonly 16 μs Cat-2 LBT, the PUSCH starting position subset may bedetermined as {symbol #(K-C2)+16 μs+TA, symbol #K}.

In order to indicate all LBT types and all PUSCH starting positions tothe UE, 2 bits are each required, so a total of 4 bits is required forthe UL grant (or DL allocation). However, when a channel access mode, oran LBT type to be used in the cell is configured/indicated in advance,the number of LBT types and PUSCH starting positions to be indicated maybe reduced. Therefore, (i) the number of bits needed when the LBT typeand the PUSCH starting position are indicated through a combinationthereof as one state as in (1-1) of Proposed Method #1 may be determinedas ceiling[log 2(total number of states that may be indicated)].Alternatively, (ii) when the LBT type and the PUSCH starting positionare indicated through individual fields, the number of bits of the fieldfor distinguishing between LBT types may be determined as ceiling[log2(the number of configured/indicated LBT types)], and the number of bitsneeded to indicate the PUSCH starting position may be determined asceiling[log 2(a maximum value among the number of PUSCH startingposition states that may be indicated to correspond to theconfigured/indicated LBT type)]. Here, the maximum value among thenumber of PUSCH starting position states that may be indicated tocorrespond to the configured/indicated LBT type is applied as follows.For example, when two LBT types, i.e., 16 μs Cat-2 LBT and Cat-4 LBT,are configured/indicated for the cell, since the number of PUSCHstarting position candidates for 16 μs Cat-2 LBT is 2 as {symbol#(K-C2)+16 μs TA, symbol #K}, and the number of PUSCH starting positioncandidates for Cat-4 LBT is 4 as {symbol #(K-C1)+25 μs, symbol#(K-C2)+16 μs+TA, symbol #(K-C3)+25 μs+TA, symbol #K}, the number ofbits of the field required to indicate the PUSCH starting position islog 2(4). The method of (ii) is applicable even when the LBT types aredistinguished through a flag as in (1-2) of Proposed Method #1 and thePUSCH starting position table is changed accordingly.

[Proposed Method #3] Method of transmitting a PUSCH as follows inconsideration of the length of a gap corresponding to an indicated PUSCHstarting position from symbol #(K-N) regardless of a TA, when a PUSCHtransmission starting symbol symbol #K, an LBT type, and the PUSCHstarting position are indicated through the SLIV in the UL grantreceived from the BS

In this case, N may be a value previously configured/indicated for eachSCS through each RMSI/RRC/DCI or a combination thereof, irrespective ofthe TA value, or may be a value defined in the standard.

(3-1) Method of transmitting the PUSCH by filling a gap between theindicated PUSCH starting position and symbol #K indicated through theSLIV with a CP of symbol #K, based on the previouslyconfigured/indicated/defined N value for each SCS, when the UE succeedsin LBT according to the indicated type

However, when there is no gap between the PUSCH starting position andsymbol #K, the UE may immediately transmit the PUSCH without CPE.

(3-2) Method of regarding related scheduling to be invalid anddiscarding DCI (UL grant) thereof or processing related scheduling as anerror case, when a value obtained by adding the gap corresponding to theindicated PUSCH starting position to symbol #(K-N) exceeds symbol #K,which is the PUSCH transmission starting symbol indicated through theSLIV

In LTE eLAA, one of 4 PUSCH starting positions {symbol #0, symbol #0+25μs, symbol #0+25 μs+TA, symbol #1} may be indicated through 2 bits inthe UL grant. Thereamong, the PUSCH starting positions present betweensymbol #0 and symbol #1, e.g., symbol #0+25 μs, may be indicated whentransmission of a previous subframe is UL, and symbol #0+25 μs+TA may beindicated when transmission of the previous subframe is DL. Uponsucceeding in LBT, the UE transmits the PUSCH by filling the gap betweenthe indicated PUSCH starting position and symbol #1 through CPE ofsymbol #1. The reason is that, when the PUSCH starting position presentbetween symbol #0 and symbol #1 is indicated to the UE and the UEsucceeds in LBT so that the UE attempts to start transmission fromsymbol #1, another node (e.g., Wi-Fi) may determine that there is notransmission in a gap between {symbol #0+25 μs} and {symbol #1} or a gapbetween {symbol #0+25 μs+TA} and {symbol #1} and occupy a channel in thegap.

Similarly, in NR-unlicensed (NR-U), when one of the PUSCH startingpositions present between symbol #K indicated through the SLIV andsymbol #(K-N) defined by the previously configured/indicated/defined Nvalue for each SCS is indicated, that is, when one of {symbol #(K-N)+16μs, symbol #(K-N)+16 μs+TA, symbol #(K-N)+25 μs, symbol #(K-N)+25 μs+TA}is indicated, the UE may transmit the PUSCH by filling a gap betweensymbol #K and the indicated PUSCH starting position through CPE.

FIG. 10 illustrates the length of CPE when a PUSCH starting position fora 15-kHz SCS is indicated. Referring to FIG. 10 , if a PUSCHtransmission starting symbol indicated through the SLIV is OS #1 andPUSCH starting positions a, b, c, or d are indicated in a symbol (i.e.,OS #0) duration prior to symbol OS #1 after the UE performs DL receptionor UL transmission (i.e., the PUSCH starting positions are indicatedbetween symbol #0 and symbol #1 if the PUSCH starting symbol indicatedthrough the SLIV is symbol #0), the UE may transmit the PUSCH by fillinga gap between the PUSCH starting position and OS #1 through CPE.

As an example, when the N value is configured/indicated/defined as 1regardless of a TA value, since the length of one OFDM symbol for the15-kHz SCS is approximately 70 μs, the case in which the length of a gapcorresponding to each PUSCH starting position exceeds symbol #K may notoccur in consideration of a typical TA value even when symbol #(K-N) isadded to one of {16 μs, 16 μs+TA, 25 μs, 25 μs+TA}.

However, if the TA value is very large so that the value of ({25μs+TA}+gap) from symbol #(K-N) exceeds symbol #K, the UE may determinethat related scheduling is not valid as in (3-2) and disregardcorresponding DCI (UL grant) or process related scheduling as an errorcase.

In the case of a 30-kHz SCS, the length of one OFDM symbol length isabout 33 μs and, in the case of a 60-kHz SCS, the length of one OFDMsymbol is about 16 μs. Therefore, the case in which the length of thegap corresponding to each PUSCH starting position exceeds symbol #Kaccording to the configured/indicated/defined N value when symbol #(K-N)is added to one of {16 μs, 16 μs+TA, 25 μs, 25 μs+TA} may occur.

The N value of each state may be determined based on a gap correspondingto a specific PUSCH starting position regardless of a TA. For example,the N value defined in the standard may be predefined for each PUSCHstarting position of each SCS as follows.

15 kHz: {symbol #(K−1)+16 μs, symbol #(K−1)+16 μs+TA, symbol #(K−1)+25μs, symbol #(K−1)+25 μs+TA, symbol #K}

30 kHz: {symbol #(K−1)+16 μs, symbol #(K−1)+16 μs+TA, symbol #(K−1)+25μs, symbol #(K−2)+25 μs+TA, symbol #K}

60 kHz: {symbol #(K−2)+16 μs, symbol #(K−2)+16 μs+TA, symbol #(K−3)+25μs, symbol #(K−3)+25 μs+TA, symbol #K}

If a specific PUSCH starting position defined based on the N valuedetermined in the standard exceeds symbol #K due to an actual TA value,the UE may consider that related scheduling is invalid and discard theDCI (UL grant) or process related scheduling as an error case.

FIG. 11 illustrates the length of CPE when each PUSCH starting positionfor a 30-kHz SCS is indicated.

Referring to FIG. 11 , if a PUSCH starting symbol for the 30-kHz SCSindicated through the SLIV is OS #1 and a PUSCH starting position isindicated in a symbol (i.e., OS #0) duration prior to symbol OS #1 afterthe UE performs DL reception or UL transmission (i.e., the PUSCHstarting position is indicated between symbol #0 and symbol #1 when thePUSCH starting symbol indicated through the SLIV is symbol #0), the UEmay transmit the PUSCH by filling a gap between the PUSCH startingposition and OS #1 through CPE.

As an example, when the N value is configured/indicated/defined as 1regardless of the TA value, since the length of one OFDM symbol for the30-kHz SCS is approximately 33 μs, the case in which the length of a gapcorresponding to each PUSCH starting position exceeds symbol #1 mayoccur according to the TA value. For example, the length of the gapcorresponding to the PUSCH starting position is indicated as {25 μs+TA}among {16 μs, 16 μs+TA, 25 μs, 25 μs+TA}, the case in which the lengthof the gap exceeds symbol #1 may occur according to the TA value. Inthis case, the UE may determine that related scheduling is not valid asin (3-2) and disregard corresponding DCI (UL grant) or process relatedscheduling as an error case.

[Proposed Method #4] Method of calculating an N value, which is areference of the PUSCH starting position, according to the TA value andtransmitting the PUSCH, when the PUSCH transmission starting symbolsymbol #K, the LBT type, and the PUSCH starting position are indicatedthrough the SLIV in the UL grant by the BS

The N value may be configured not to exceed symbol #K when a gapcorresponding to an indicated PUSCH starting position is added to symbol#(K-N), or N may be configured not to exceed the length of one OFDMsymbol based on a corresponding SCS when the UE transmits the PUSCH byfilling a duration from the PUSCH starting position to symbol #K throughCPE.

The UE may calculate the N value for each SCS and transmit the PUSCH byfilling a gap between the indicated PUSCH starting position and symbol#K indicated through the SLIV with a CP of symbol #K (i.e. CPE).

However, if there is no gap between the PUSCH starting position andsymbol #K, the PUSCH may be immediately transmitted without CPE.

If one of PUSCH starting positions present between symbol #K indicatedthrough the SLIV and symbol #(K-N) according to the N value calculatedbased on the TA value for each SCS is indicated to the UE, the UE maytransmit the PUSCH by filling a gap between symbol #K and the indicatedPUSCH starting position with the CP of symbol #K. Since the length ofCPE may vary according to the N value, the BS may calculate andconfigure the N value such that the length of CPE for each SCS does notexceed the length of one OFDM symbol. In addition, the BS may configurethe N value such that a specific PUSCH starting position does not exceedsymbol #K indicated through SLIV according to the TA value.

For example, in FIG. 11 , if the UE configures the N value so as not toexceed the PUSCH starting symbol indicated through the SLIV inconsideration of the TA value, the N value may be set to 2.

That is, the present proposed method is related to a method in which thelength of CPE does not exceed the length of one OFDM symbol. Since thelength of one OFDM symbol differs according to each SCS, the length ofCPE may be configured not to exceed the length of one OFDM symbol basedon each SCS. As an example, the length of one OFDM symbol may be thesymbol length of symbol #K indicated through the SLIV to the UE withrespect to a configured SCS.

The present proposal provides a method of determining a parameter, i.e.,the N value, such that the length of CPE does not exceed the length ofone OFDM symbol. More specifically, the present proposal provides amethod of determining the parameter N value such that the length of CPEdoes not exceed symbol #K, which is the PUSCH starting symbol indicatedthrough the SLIV.

Comparing Proposed Method #4 with the Proposed Method #1 describedabove, the length of the CPE, i.e., the N value as well, is indicated tothe UE in Proposed Method #1, whereas Proposed Method #4 is related todetermination of the N value by the UE when the N value is not indicatedto the UE (e.g., an RACH procedure or fallback DCI). Specifically, the Nvalue is determined as an integer value such that the length of CPE doesnot exceed the length of one OFDM symbol.

For example, when the N value is not configured through a higher layersignal, the N value may be determined as a maximum integer value suchthat the length of CPE does not exceed the length of one OFDM symbol.

Since the length of one OFDM symbol differs according to each SCS, theSCS should be considered in determining the N value. On the other hand,the TA value should be considered for UL transmission. Therefore, theSCS and the TA value of the UE should be considered in determining thelength of CPE in relation to the PUSCH starting position. In addition,in a system supporting a U-band applied to an embodiment of the presentdisclosure, a CAP type, i.e., the length of a channel sensing durationaccording to the CAP type, may also be considered in determining the Nvalue.

As an example, the length of CPE is calculated in consideration of theTA value of the UE and the N value which is determined by consideringthe SCS and the CAP type. When the calculated length of CPE exceeds thelength of one OFDM symbol, the length of one symbol may be determined asthe length of CPE.

The UE may start PUSCH transmission at a position earlier by the lengthof CPE than symbol #K.

Referring to FIGS. 12 and 13 , the UE may receive information about aPUSCH starting symbol #K (S1210 and 1310) and transmit a PUSCH at aspecific position based on a result of performing a CAP (S1220 and1330). For example, symbol #K and a CAP type may be indicated by DCI.The specific position may be ahead of symbol #K and may be a positionearlier by the length of CPE. That is, the UE may start PUSCHtransmission at a position earlier than symbol #K by the length of CPE.The N value, which is a parameter related to the length of CPE, may beconfigured through a higher layer signal as in Proposed Method #1 or maybe determined as an integer value that causes the length of CPE not toexceed the length of one OFDM symbol as in Proposed Method #4. Thelength of one OFDM symbol length may differ according to an SCS and maybe, for example, the length of symbol #K. That is, the parameter N valuemay be an integer value (e.g., a maximum integer value) that causes thelength of CPE not to exceed symbol #K. The UE may determine the PUSCHstarting position based on the length of CPE (S1320). As an example, theparameter may be determined based on the SCS and CAP type, and thelength of CPE may be determined based on the parameter and the TA value.The UE may start PUSCH transmission at a position earlier than symbol #Kby the length of CPE.

[Proposed Method #5] Although the BS has indicated CPE in considerationof the LBT type (or CAP type) and the TA value of the UE upon schedulingthe PUSCH through the UL grant for the UE, if a CPE duration calculatedby the UE becomes different from a value intended originally by the BSdue to an inaccurate TA value so that a gap between transmissions doesnot match the LBT type indicated to the UE, the UE may operate asfollows.

(5-1) Method of performing 25 μs Cat-2 LBT before 25 μs from a ULstarting time actually calculated by the UE and transmitting the PUSCH,when an originally indicated LBT type is 25 μs Cat-2 LBT and a gapbetween actual transmissions is greater than 25 μs

(5-2) Method of performing 16 μs Cat-2 LBT before 16 μs from the ULstarting time actually calculated by the UE and transmitting the PUSCH,when the originally indicated LBT type is 16 μs Cat-2 LBT and the gapbetween actual transmissions is greater than 16 μs

(5-3) Method of performing 25 μs Cat-2 LBT before 25 μs from the ULstarting time actually calculated by the UE and transmitting the PUSCH,when the originally indicated LBT type is 16 μs Cat-2 LBT and the gapbetween actual transmissions is greater than 25 μs

(5-4) Method of performing 16 μs Cat-2 LBT before 16 μs from the ULstarting time actually calculated by the UE and transmitting the PUSCHwhen an originally indicated LBT type is 16 μs Cat-1 LBT and the gapbetween actual transmissions is greater than 16 μs

(5-5) Method of performing 25 μs Cat-2 LBT before 25 μs from the ULstarting time actually calculated by the UE and transmitting the PUSCH,when the originally indicated LBT type is 16 μs Cat-1 LBT and the gapbetween actual transmissions is greater than 25 μs

(5-6) Method of skipping transmission of the PUSCH, when the originallyindicated LBT type is 16 μs Cat-1 LBT and the gap between actualtransmissions is greater than 16 μs

(5-7) Method of transmitting the PUSCH in Cat-1 LBT by allowing CPElonger than the length of one OFDM symbol, when the originally indicatedLBT type is 16 μs Cat-1 LBT and the gap between actual transmissions isgreater than 16 μs

The BS may indicate CPE and the LBT type considering the TA value of theUE through the UL grant during UL scheduling by tracking the TA value ofthe UE after RRC connection with the UE. However, when a TA valuemanaged by the BS and an actual TA value of the UE are different fromeach other, the length of CPE calculated based on the indication of theBS may be less than 0 or longer than the length of one OFDM symbol. Ifthe length of CPE is maintained at a value which is always greater than0 and less than the length of one OFDM symbol, the gap betweentransmissions considered by the BS during UL scheduling and the LBT typecorresponding thereto may not match an actual length of the gap.

That is, the TA value of the BS and the actual TA value of the UE may bedifferent, so that a gap before UL scheduling may be longer than thelength of a gap originally intended by the BS. For example, although theBS indicates 25 μs Cat-2 LBT under the assumption that a gap betweenimmediately preceding transmission and UL transmission to be scheduledis 25 μs by indicating CPE considering a TA value and an LBT gap, thelength of a CP required for a 25 μs gap may be greater than the lengthof one symbol when the length of the CP is calculated using the actualTA value of the UE. In this situation, if the length of the CP isrestricted not to be greater than the length of one symbol, the gapbetween immediately preceding transmission and UL transmission scheduledby the UE may be greater than 25 Therefore, since the indicated LBTtype, the actual length of the gap, and the recalculated actual ULtransmission starting time are changed, the UE may operate as in themethods of (5-1) to (5-7).

More specifically, referring to a CPE calculation part of Section 5.3.1of TS 38.211, the UE calculates Text using an equation of Table 5.3.1-1based on information indicated through the UL grant and applies a finalCPE value calculated by an equation of min (max(T_(ext), 0),T_(symb,(l-1)mod 7-2) _(μ) ^(μ)). As described above, if the requiredText value calculated by the UE based on the actual TA value is greaterthan the length of one OFDM symbol but the length of the CP of a maximumof the length of one OFDM symbol shorter than the actual required lengthaccording to the above equation is applied, the length of the gapbetween immediately previous transmission and scheduled UL transmissionmay be longer than a length intended by the BS. Therefore, in this case,the gap between the indicated LBT type and actual transmission may bedifferent, and the UE may transmit the PUSCH by applying the methods of(5-1) to (5-7).

In the case of the method of (7), since 16 μs Cat-1 LBT may be appliedonly when the length of the gap between transmissions is exactly 16 thelength of the CP longer than the length of one OFDM symbol is permittedas an exceptional case in order to allow the UE to transmit the PUSCHeven when the gap between transmissions is larger than 16 μs due torestrictions on the length of the CP.

Proposed Method #5 may be applied to other UL signals/channels thatrequire CPE, such as a PUCCH or an SRS, scheduled through DL assignment,as well as the PUSCH scheduled through the UL grant.

[Proposed Method #6] When an indicated LBT type and a gap, based on a TAvalue of the UE that the BS tracks, do not match an actual TA value ofthe UE so that CPE that exceeds the length of one symbol is needed, theUE may operate as follows.

(6-1) If an LBT type indicated by the BS or performed by the UE is Cat-4LBT, CPE of a length calculated by the CPE calculation equation definedin Section 5.3.1 of TS 38.211 may be applied, and corresponding ULtransmission may be dropped in the case of Cat-1 LBT or 16 μs or 25 μsCat-2 LBT.

(6-2) If the LBT type indicated by the BS or performed by the UE isCat-1 LBT or 16 μs or 25 μs Cat-2 LBT, the UE may indicate, to the BS,the fact that an actual gap is larger than a gap intended by the BSthrough a previously defined or configured/indicated DM-RS sequence orthrough UCI piggyback.

During UL scheduling, the BS indicates, to the UE, CPE and an LBT typenecessary for the UE in consideration of a gap with previoustransmission based on a TA value of the UE that the BS tracks. However,since an actual TA value of the UE may be different from a TA value ofthe BS, a gap between actual transmissions may be larger than a gapintended by the BS. In this case, CPE greater than one symbol may berequired.

Since the length of CPE is regulated not to exceed a maximum of thelength of one OFDM symbol, if the LBT type indicated by the BS orperformed by the UE is Cat-4 LBT, the UE may calculate Text by theequation of Table 5.3.1-1 based on information indicated through the ULgrant and applies a final CPE value calculated by the equation min(max(T_(ext), 0), T_(symb,(l-1)mod 7-2) _(μ) ^(μ)). If the LBT typeindicated by the BS or performed by the UE is Cat-1 LBT, 16 μs Cat-2, or25 μs Cat-2 LBT, since UL transmission is allowed only when the gap isexactly 16 μs or 25 μs, the UE may drop corresponding UL transmission inthe case of max(T_(ext), 0), T_(symb,(l-1)mod 7-2) _(μ) ^(μ).

When the UE performs subsequent UL transmission after performing Cat-1LBT, 16 μs Cat-2, or 25 μs Cat-2 LBT by sharing a COT obtained by the BSthrough Cat-4 LBT for DL transmission, if a gap between DL transmissionand UL transmission is exactly 16 μs or 25 μs and the COT remains afterUL transmission (e.g., DL length+UL length<COT length), multiple DL/ULswitching in which the BS may perform DL transmission again after ULtransmission may be performed. If the gap between DL transmission and ULtransmission within the COT is greater than 16 μs or 25 μs, single ULtransmission may be performed when 16 μs or 25 μs Cat-2 LBT issuccessfully performed immediately before UL transmission, andsubsequent DL transmission may not be performed even if the COT remains.Since this pause COT operation is allowed only for single DL-ULswitching transmission, if the actual length of the gap is larger than agap intended by the BS, i.e., if max(T_(ext), 0), T_(symb,(l-1)mod 7-2)_(μ) ^(μ), the BS may be informed of the fact that multiple DL/ULswitching transmission that performs DL transmission followed by ULtransmission is not possible through a DM-RS sequence which ispreviously defined in the standard or is previously configured/indicatedor through UCI piggyback. This proposal may be particularly applied whenthe LBT type indicated by the BS or performed by the UE is Cat-1 LBT, 16μs Cat-2, or 25 μs Cat-2 LBT.

[Proposed Method #7] Method of configuring a reference duration T in thefollowing methods and reflecting HARQ-ACK for the PUSCH in the referenceduration T to adjust a CWS, when the UE intends to determine thereference duration T for CWS adjustment with respect to a UE-initiatedCOT in a carrier aggregation (CA) situation in which a plurality ofcells having different SCSs is configured

(7-1) Method of configuring up to a boundary of the nearest slot basedon a cell in which a unicast PUSCH is transmitted through all resourcesallocated to a PUSCH as T

(7-2) Method of configuring up to a boundary of the nearest slot amongany cells configured with CA as T

(7-3) Method of configuring up to a boundary of a slot nearest a cellhaving the smallest or largest SCS as T

(7-4) Method of configuring up to a boundary of a slot nearest aspecific cell configured/indicated by the BS through RRC, DCI, or acombination of RRC and DCI as T

(7-5) Method of configuring up to a boundary of a slot nearest a cellhaving the lowest index or the highest index as T

However, the reference duration T for CWS adjustment in a cell having aspecific SCS may be a first occurring one among a duration from thestart of the COT to the end of the first slot with at least one PUSCHtransmitted through all resources allocated to the PUSCH and a durationfrom the start of the COT to the end of the first UL burst includingPUSCH(s) transmitted by the UE through all resources allocated to thePUSCH. Although there is channel occupancy with the PUSCH, if the PUSCHis not transmitted through all resources allocated to the PUSCH, thefirst UL burst duration by the UE in channel occupancy including thePUSCH(s) may be the reference duration T for CWS adjustment.

When the UE receives data scheduling from a single cell, a duration fromthe start of a UE-initiated COT to a slot with a unicast PUSCHtransmitted through all resources allocated to the PUSCH among PUSCHsconstituting a UL burst may be configured as the reference duration T.However, when CA with which the UE may receive scheduling from aplurality of cells having different SCSs is configured, a slot boundarymay be different according to each cell. In NR, since the UE may receiveCBG-based scheduling or non-slot-based scheduling in addition toslot-based scheduling, a unicast PUSCH transmitted through all resourcesallocated to the PUSCH occurs in a cell having a specific SCS.Accordingly, if it is desired to configure the reference duration T, thereference duration T may not be aligned with a slot boundary of a cellhaving another SCS. In this case, promise/definition as in the methodsof (7-1) to (7-5) above may be required to determine up to which slotfor each cell should be included in the reference duration T.

FIG. 14 illustrates a situation in which three cells having differentSCSs are configured with CA and UL transmission is scheduled for the UE.

Referring to FIG. 14 , cells A, B, and C having different SCSs areconfigured with CA and UL transmission is scheduled for the UE. A PUSCHon which TB2 transmitted in a mini-slot is transmitted through allresources allocated to the PUSCH occurs in the 30-kHz cell B, and up toa boundary of the nearest slot based on a cell transmitted through allresources allocated to the PUSCH is configured as the reference durationT as in the method of (7-1). That is, TB 2 transmitted through allresources allocated to the PUSCH occurs in the middle of the first slotof cell B so that the reference duration T including a duration to theend of the slot including TB 2 based on an SCS of 30 kHz is configured.In the case of cell C, since TB 5 and TB 6 belong to the configuredreference duration T, the reference duration T may be reflected in CWSadjustment of the UE according to a decoding result for TB 2, TB 3, TB5, and TB 6 (whether retransmission scheduling through an NDI isperformed).

FIG. 15 illustrates another situation in which three cells havingdifferent SCSs are configured with CA and UL transmission is scheduledfor the UE.

If the reference duration T is configured as in the method of (7-2) inthe situation as illustrated FIG. 15 , up to a slot in which TB 5 ofcell C is scheduled based on TB 2 may be configured as T.

FIG. 16 illustrates another situation in which three cells havingdifferent SCSs are configured with CA and UL transmission is scheduledfor the UE.

If the reference duration T is configured based on the smallest SCS inthe method of (7-3), up to a slot including TB 1 of cell A is configuredas the reference duration T, so that all TBs are included in thereference duration T. If the reference duration T is configured based ona large SCS, up to a slot in which TB 5 of cell C is scheduled may beconfigured as the reference duration T as in the method of (7-2).

The BS may previously indicate/configure, to/for the UE, whether toconfigure the reference duration T based on a slot boundary of any cellthrough RRC, DCI, or a combination of RRC and DCI as in (7-4).Alternatively, as in (7-5), the reference duration T may be configuredbased on a slot boundary nearest a cell having the smallest or largestcell index among a plurality of cells configured with CA.

[Proposed Method #8] When the UE receives, from the BS, a minimumduration D1 consumed until a UL grant containing feedback (e.g., an NDIor CBG transmission information (CBGTI)) for the PUSCH is receivedthrough a higher layer signal such as RRC and then the UE desires toconfigure the reference duration T in the latest UE-initiated COT beforen-D1 for UL CWS adjustment, if there is no PUSCH transmitted through allresources allocated to the PUSCH among unicast PUSCHs transmitted fromthe start of a corresponding COT to n-D1 in a COT (in other words, onlya PUSCH transmitted through only some of all resources allocated to thePUSCH among the unicast PUSCHs transmitted from the start of the COT ton-D1), the reference duration T may be configured as follows and bereflected in CWS adjustment.

(8-1) Method of configuring the reference period T based only onPUSCH(s) transmitted through some resources allocated to the PUSCH amongPUSCH(s) transmitted in the latest UE-initiated COT before n-D1

(8-2) Method of configuring the reference duration T based on a feedbackresult within the reference duration T by returning back to the latest(immediately previous) UE-initiated COT transmitted earlier

Here, D1 is a time from the last symbol of the PUSCH to a start symbolof the UL grant containing feedback and may be configured in units ofslots or symbols. If D1 is not configured but a minimum duration D2consumed until CG-DFI is received after CG-PUSCH transmission isconfigured, D2 may be used as the D1 value. Even if the D1 value isconfigured, the D1 value may be replaced with the D2 value according toa previous configuration/indication or previous definition in thestandard, or the D1 value may be determined as a function of the D1 andD2 values, such as min(D1, D2) or max(D1, D2).

For UE-initiated channel occupancy, the reference duration for CWSadjustment may be defined as follows. For channel occupancy with thePUSCH and a set of LBT bandwidths in which a single contention window ismaintained, the reference duration for CWS adjustment may be the firstgenerated duration among a duration from the start of channel occupancyto the end of the first slot in which at least one PUSCH is transmittedthrough all resources allocated to the PUSCH and a duration from thestart of channel occupancy to the end of the first transmission burstincluding PUSCH(s) transmitted by the UE through all resources allocatedto the PUSCH. If there is channel occupation with the PUSCH but thePUSCH is not transmitted through all resources allocated to the PUSCH,the duration of the first transmission burst by the UE in channeloccupation including PUSCH(s) may be the reference duration for CWSadjustment.

The UE may receive, from the BS, the minimum duration D1 required toreceive the UL grant containing feedback for the PUSCH transmittedthereby through a higher layer signal such as RRC. Upon receiving the ULgrant, the UE may configure, for CWS adjustment, the reference durationT up to a PUSCH slot transmitted through all resources allocated to thePUSCH among PUSCHs transmitted in the latest UE-initiated COT beforen-D1 and adjust a CWS based on a feedback result for the PUSCH withinthe reference duration. However, if the PUSCH transmitted through allresources allocated to the PUSCH among the PUSCHs transmitted in thelatest UE initiated COT before n-D1 does not exist at a CWS adjustmenttiming, the reference duration T may not be configured by definition ofthe reference duration.

FIG. 17 exemplarily illustrates a CWS adjustment timing of the UE andPUSCHs in the latest UE-initiated COT before the configured D1.

In a situation of FIG. 17 , the UE receives a UL grant in slot #5 whenD1=4 (slots) is configured and, among PUSCHs transmitted within thelatest UE-initiated COT before D1 in order to perform CWS adjustment,PUSCHs transmitted with HARQ ID #0 and HARQ ID #1 are not transmittedthrough all resources allocated to the PUSCH, and a PUSCH transmittedwith HARQ ID #2 is transmitted through all resources allocated to thePUSCH. In this example, since there is no PUSCH transmitted through allresources allocated to the PUSCH in the latest UE-initiated COT beforen-D1 from a time when the UE receives the UL grant, the referenceduration T may not be configured according to the definition of thereference duration.

In this case, the UE may adjust the CWS by (8-1) or (8-2) of theproposed method. In the case of (8-1), although the reference duration Tis not configured because there is no PUSCH transmitted through allresources allocated to the PUSCH in the latest UE-initiated COT beforen-D1, PUSCH(s) transmitted through some resources are configured as thereference duration T (in the example of FIG. 11 , a duration up to thePUSCH transmitted with HARQ ID #0 is configured as T). In the case of(8-2), the CWS is adjusted based on a feedback result within thereference duration T by returning back to a UL burst transmitted earlierthan the latest UE-initiated COT before n-D1.

The UE may perform a procedure of accessing a network to perform thedescribed/proposed procedures and/or methods of the present disclosure(FIGS. 10 to 17 ). For example, while accessing a network (e.g., a BS),the UE may receive system information and configuration information,needed to perform the above described/proposed procedures and/ormethods, and store the system information and the configurationinformation in a memory. The configuration information necessary for thepresent disclosure may be received through higher-layer (e.g., RRC, MAC,or layer) signaling.

FIG. 18 is a diagram illustrating an initial network access andsubsequent communication process. In NR, a physical channel and an RSmay be transmitted by beamforming. When beamforming-based signaltransmission is supported, beam management may follow, for beamalignment between a BS and a UE. Further, a signal proposed by thepresent disclosure may be transmitted/received by beamforming. InRRC_IDLE mode, beam alignment may be performed based on an SSB, whereasin RRC_CONNECTED mode, beam alignment may be performed based on a CSI-RS(in DL) and an SRS (in UL). On the contrary, when beamforming-basedsignal transmission is not supported, beam-related operations in thefollowing description may be skipped.

Referring to FIG. 18 , a BS (e.g., eNB) may periodically transmit an SSB(S2102). The SSB includes a PSS/SSS/PBCH. The SSB may be transmitted bybeam sweeping (see FIG. D5). The PBCH may include a master informationblock (MSB), and the MIB may include scheduling information forremaining minimum system information (RMSI). The BS may then transmitthe RMSI and other system information (OSI) (S2104). The RMSI mayinclude information required for initial access to the BS (e.g., PRACHconfiguration information). After detecting SSBs, the UE identifies thebest SSB. The UE may then transmit an RACH preamble (Message 1; Msg1) inPRACH resources linked/corresponding to the index (i.e., beam) of thebest SSB (S2106). The beam direction of the RACH preamble is associatedwith the PRACH resources. Association between PRACH resources (and/orRACH preambles) and SSBs (SSB indexes) may be configured by systeminformation (e.g., RMSI). Subsequently, in an RACH procedure, the BS maytransmit a random access response (RAR) (Msg2) in response to the RACHpreamble (S2108), the UE may transmit Msg3 (e.g., RRC ConnectionRequest) based on a UL grant included in the RAR (S2110), and the BS maytransmit a contention resolution message (Msg4) (S2120). Msg4 mayinclude RRC Connection Setup.

When an RRC connection is established between the BS and the UE in theRACH procedure, beam alignment may subsequently be performed based on anSSB/CSI-RS (in DL) and an SRS (in UL). For example, the UE may receivean SSB/CSI-RS (S2114). The SSB/CSI-RS may be used for the UE to generatea beam/CSI report. The BS may request the UE to transmit a beam/CSIreport, by DCI (S2116). In this case, the UE may generate a beam/CSIreport based on the SSB/CSI-RS and transmit the generated beam/CSIreport to the BS on a PUSCH/PUCCH (S2118). The beam/CSI report mayinclude a beam measurement result, information about a preferred beam,and so on. The BS and the UE may switch beams based on the beam/CSIreport (S2120 a and S2120 b).

Subsequently, the UE and the BS may perform the above-described/proposedprocedures and/or methods (FIG. 10 to FIG. 17 ). For example, the UE andthe BS may transmit a wireless signal by processing information storedin a memory or may process a received wireless signal and store theprocessed signal in a memory according to the proposal of the presentdisclosure, based on configuration information obtained in a networkaccess process (e.g., a system information acquisition process, an RRCconnection process on an RACH, and so on). The wireless signal mayinclude at least one of a PDCCH, a PDSCH, or an RS on DL and at leastone of a PUCCH, a PUSCH, or an SRS on UL.

Each of the above-mentioned proposed methods may be combined and appliedtogether with other proposed methods unless they conflict with eachother.

The various descriptions, functions, procedures, proposals, methods,and/or operation flowcharts of the present disclosure described hereinmay be applied to, but not limited to, various fields requiring wirelesscommunication/connectivity (e.g., 5G) between devices.

More specific examples will be described below with reference to thedrawings. In the following drawings/description, like reference numeralsdenote the same or corresponding hardware blocks, software blocks, orfunction blocks, unless otherwise specified.

FIG. 19 illustrates a communication system 1 applied to the presentdisclosure.

Referring to FIG. 19 , the communication system 1 applied to the presentdisclosure includes wireless devices, BSs, and a network. A wirelessdevice is a device performing communication using radio accesstechnology (RAT) (e.g., 5G NR (or New RAT) or LTE), also referred to asa communication/radio/5G device. The wireless devices may include, notlimited to, a robot 100 a, vehicles 100 b-1 and 100 b-2, an extendedreality (XR) device 100 c, a hand-held device 100 d, a home appliance100 e, an IoT device 100 f, and an artificial intelligence (AI)device/server 400. For example, the vehicles may include a vehiclehaving a wireless communication function, an autonomous driving vehicle,and a vehicle capable of vehicle-to-vehicle (V2V) communication. Herein,the vehicles may include an unmanned aerial vehicle (UAV) (e.g., adrone). The XR device may include an augmented reality (AR)/virtualreality (VR)/mixed reality (MR) device and may be implemented in theform of a head-mounted device (HMD), a head-up display (HUD) mounted ina vehicle, a television (TV), a smartphone, a computer, a wearabledevice, a home appliance, a digital signage, a vehicle, a robot, and soon. The hand-held device may include a smartphone, a smartpad, awearable device (e.g., a smartwatch or smartglasses), and a computer(e.g., a laptop). The home appliance may include a TV, a refrigerator, awashing machine, and so on. The IoT device may include a sensor, asmartmeter, and so on. For example, the BSs and the network may beimplemented as wireless devices, and a specific wireless device 200 amay operate as a BS/network node for other wireless devices.

The wireless devices 100 a to 100 f may be connected to the network 300via the BSs 200. An AI technology may be applied to the wireless devices100 a to 100 f, and the wireless devices 100 a to 100 f may be connectedto the AI server 400 via the network 300. The network 300 may beconfigured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g.,NR) network. Although the wireless devices 100 a to 100 f maycommunicate with each other through the BSs 200/network 300, thewireless devices 100 a to 100 f may perform direct communication (e.g.,sidelink communication) with each other without intervention of theBSs/network. For example, the vehicles 100 b-1 and 100 b-2 may performdirect communication (e.g. V2V/vehicle-to-everything (V2X)communication). The IoT device (e.g., a sensor) may perform directcommunication with other IoT devices (e.g., sensors) or other wirelessdevices 100 a to 100 f.

Wireless communication/connections 150 a, 150 b, and 150 c may beestablished between the wireless devices 100 a to 100 f/BS 200 andbetween the BSs 200. Herein, the wireless communication/connections maybe established through various RATs (e.g., 5G NR) such as UL/DLcommunication 150 a, sidelink communication 150 b (or, D2Dcommunication), or inter-BS communication (e.g. relay or integratedaccess backhaul (IAB)). Wireless signals may be transmitted and receivedbetween the wireless devices, between the wireless devices and the BSs,and between the BSs through the wireless communication/connections 150a, 150 b, and 150 c. For example, signals may be transmitted and receivedon various physical channels through the wirelesscommunication/connections 150 a, 150 b and 150 c. To this end, at leasta part of various configuration information configuring processes,various signal processing processes (e.g., channel encoding/decoding,modulation/demodulation, and resource mapping/demapping), and resourceallocation processes, for transmitting/receiving wireless signals, maybe performed based on the various proposals of the present disclosure.

FIG. 20 illustrates wireless devices applicable to the presentdisclosure.

Referring to FIG. 20 , a first wireless device 100 and a second wirelessdevice 200 may transmit wireless signals through a variety of RATs(e.g., LTE and NR). {The first wireless device 100 and the secondwireless device 200} may correspond to {the wireless device 100 x andthe BS 200} and/or {the wireless device 100 x and the wireless device100 x} of FIG. 19 .

The first wireless device 100 may include one or more processors 102 andone or more memories 104, and further include one or more transceivers106 and/or one or more antennas 108. The processor(s) 102 may controlthe memory(s) 104 and/or the transceiver(s) 106 and may be configured toimplement the descriptions, functions, procedures, proposals, methods,and/or operation flowcharts disclosed in this document. For example, theprocessor(s) 102 may process information in the memory(s) 104 togenerate first information/signals and then transmit wireless signalsincluding the first information/signals through the transceiver(s) 106.The processor(s) 102 may receive wireless signals including secondinformation/signals through the transceiver(s) 106 and then storeinformation obtained by processing the second information/signals in thememory(s) 104. The memory(s) 104 may be connected to the processor(s)102 and may store various pieces of information related to operations ofthe processor(s) 102. For example, the memory(s) 104 may store softwarecode including instructions for performing all or a part of processescontrolled by the processor(s) 102 or for performing the descriptions,functions, procedures, proposals, methods, and/or operation flowchartsdisclosed in this document. The processor(s) 102 and the memory(s) 104may be a part of a communication modem/circuit/chip designed toimplement RAT (e.g., LTE or NR). The transceiver(s) 106 may be connectedto the processor(s) 102 and transmit and/or receive wireless signalsthrough the one or more antennas 108. Each of the transceiver(s) 106 mayinclude a transmitter and/or a receiver. The transceiver(s) 106 may beinterchangeably used with radio frequency (RF) unit(s). In the presentdisclosure, the wireless device may be a communicationmodem/circuit/chip.

The second wireless device 200 may include one or more processors 202and one or more memories 204, and further include one or moretransceivers 206 and/or one or more antennas 208. The processor(s) 202may control the memory(s) 204 and/or the transceiver(s) 206 and may beconfigured to implement the descriptions, functions, procedures,proposals, methods, and/or operation flowcharts disclosed in thisdocument. For example, the processor(s) 202 may process information inthe memory(s) 204 to generate third information/signals and thentransmit wireless signals including the third information/signalsthrough the transceiver(s) 206. The processor(s) 202 may receivewireless signals including fourth information/signals through thetransceiver(s) 106 and then store information obtained by processing thefourth information/signals in the memory(s) 204. The memory(s) 204 maybe connected to the processor(s) 202 and store various pieces ofinformation related to operations of the processor(s) 202. For example,the memory(s) 204 may store software code including instructions forperforming all or a part of processes controlled by the processor(s) 202or for performing the descriptions, functions, procedures, proposals,methods, and/or operation flowcharts disclosed in this document. Theprocessor(s) 202 and the memory(s) 204 may be a part of a communicationmodem/circuit/chip designed to implement RAT (e.g., LTE or NR). Thetransceiver(s) 206 may be connected to the processor(s) 202 and transmitand/or receive wireless signals through the one or more antennas 208.Each of the transceiver(s) 206 may include a transmitter and/or areceiver. The transceiver(s) 206 may be interchangeably used with RFunit(s). In the present disclosure, the wireless device may be acommunication modem/circuit/chip.

Now, hardware elements of the wireless devices 100 and 200 will bedescribed in greater detail. One or more protocol layers may beimplemented by, not limited to, one or more processors 102 and 202. Forexample, the one or more processors 102 and 202 may implement one ormore layers (e.g., functional layers such as physical (PHY), mediumaccess control (MAC), radio link control (RLC), packet data convergenceprotocol (PDCP), RRC, and service data adaptation protocol (SDAP)). Theone or more processors 102 and 202 may generate one or more protocoldata units (PDUs) and/or one or more service data Units (SDUs) accordingto the descriptions, functions, procedures, proposals, methods, and/oroperation flowcharts disclosed in this document. The one or moreprocessors 102 and 202 may generate messages, control information, data,or information according to the descriptions, functions, procedures,proposals, methods, and/or operation flowcharts disclosed in thisdocument and provide the messages, control information, data, orinformation to one or more transceivers 106 and 206. The one or moreprocessors 102 and 202 may generate signals (e.g., baseband signals)including PDUs, SDUs, messages, control information, data, orinformation according to the descriptions, functions, procedures,proposals, methods, and/or operation flowcharts disclosed in thisdocument and provide the generated signals to the one or moretransceivers 106 and 206. The one or more processors 102 and 202 mayreceive the signals (e.g., baseband signals) from the one or moretransceivers 106 and 206 and acquire the PDUs, SDUs, messages, controlinformation, data, or information according to the descriptions,functions, procedures, proposals, methods, and/or operation flowchartsdisclosed in this document.

The one or more processors 102 and 202 may be referred to ascontrollers, microcontrollers, microprocessors, or microcomputers. Theone or more processors 102 and 202 may be implemented by hardware,firmware, software, or a combination thereof. For example, one or moreapplication specific integrated circuits (ASICs), one or more digitalsignal processors (DSPs), one or more digital signal processing devices(DSPDs), one or more programmable logic devices (PLDs), or one or morefield programmable gate arrays (FPGAs) may be included in the one ormore processors 102 and 202. The descriptions, functions, procedures,proposals, methods, and/or operation flowcharts disclosed in thisdocument may be implemented using firmware or software, and the firmwareor software may be configured to include the modules, procedures, orfunctions. Firmware or software configured to perform the descriptions,functions, procedures, proposals, methods, and/or operation flowchartsdisclosed in this document may be included in the one or more processors102 and 202 or may be stored in the one or more memories 104 and 204 andexecuted by the one or more processors 102 and 202. The descriptions,functions, procedures, proposals, methods, and/or operation flowchartsdisclosed in this document may be implemented using firmware or softwarein the form of code, an instruction, and/or a set of instructions.

The one or more memories 104 and 204 may be connected to the one or moreprocessors 102 and 202 and store various types of data, signals,messages, information, programs, code, instructions, and/or commands.The one or more memories 104 and 204 may be configured to includeread-only memories (ROMs), random access memories (RAMs), electricallyerasable programmable read-only memories (EPROMs), flash memories, harddrives, registers, cash memories, computer-readable storage media,and/or combinations thereof. The one or more memories 104 and 204 may belocated at the interior and/or exterior of the one or more processors102 and 202. The one or more memories 104 and 204 may be connected tothe one or more processors 102 and 202 through various technologies suchas wired or wireless connection.

The one or more transceivers 106 and 206 may transmit user data, controlinformation, and/or wireless signals/channels, mentioned in the methodsand/or operation flowcharts of this document, to one or more otherdevices. The one or more transceivers 106 and 206 may receive user data,control information, and/or wireless signals/channels, mentioned in thedescriptions, functions, procedures, proposals, methods, and/oroperation flowcharts disclosed in this document, from one or more otherdevices. For example, the one or more transceivers 106 and 206 may beconnected to the one or more processors 102 and 202 and transmit andreceive wireless signals. For example, the one or more processors 102and 202 may perform control so that the one or more transceivers 106 and206 may transmit user data, control information, or wireless signals toone or more other devices. The one or more processors 102 and 202 mayperform control so that the one or more transceivers 106 and 206 mayreceive user data, control information, or wireless signals from one ormore other devices. The one or more transceivers 106 and 206 may beconnected to the one or more antennas 108 and 208 and the one or moretransceivers 106 and 206 may be configured to transmit and receive userdata, control information, and/or wireless signals/channels, mentionedin the descriptions, functions, procedures, proposals, methods, and/oroperation flowcharts disclosed in this document, through the one or moreantennas 108 and 208. In this document, the one or more antennas may bea plurality of physical antennas or a plurality of logical antennas(e.g., antenna ports). The one or more transceivers 106 and 206 mayconvert received wireless signals/channels from RF band signals intobaseband signals in order to process received user data, controlinformation, and wireless signals/channels using the one or moreprocessors 102 and 202. The one or more transceivers 106 and 206 mayconvert the user data, control information, and wirelesssignals/channels processed using the one or more processors 102 and 202from the baseband signals into the RF band signals. To this end, the oneor more transceivers 106 and 206 may include (analog) oscillators and/orfilters.

FIG. 21 illustrates another example of a wireless device applied to thepresent disclosure. The wireless device may be implemented in variousforms according to a use case/service (refer to FIG. 18 ).

Referring to FIG. 21 , wireless devices 100 and 200 may correspond tothe wireless devices 100 and 200 of FIG. 19 and may be configured toinclude various elements, components, units/portions, and/or modules.For example, each of the wireless devices 100 and 200 may include acommunication unit 110, a control unit 120, a memory unit 130, andadditional components 140. The communication unit 110 may include acommunication circuit 112 and transceiver(s) 114. For example, thecommunication circuit 112 may include the one or more processors 102 and202 and/or the one or more memories 104 and 204 of FIG. 21 . Forexample, the transceiver(s) 114 may include the one or more transceivers106 and 206 and/or the one or more antennas 108 and 208 of FIG. 21 . Thecontrol unit 120 is electrically connected to the communication unit110, the memory 130, and the additional components 140 and providesoverall control to the wireless device. For example, the control unit120 may control an electric/mechanical operation of the wireless devicebased on programs/code/instructions/information stored in the memoryunit 130. The control unit 120 may transmit the information stored inthe memory unit 130 to the outside (e.g., other communication devices)via the communication unit 110 through a wireless/wired interface orstore, in the memory unit 130, information received through thewireless/wired interface from the outside (e.g., other communicationdevices) via the communication unit 110.

The additional components 140 may be configured in various mannersaccording to type of the wireless device. For example, the additionalcomponents 140 may include at least one of a power unit/battery,input/output (I/O) unit, a driving unit, and a computing unit. Thewireless device may be implemented in the form of, not limited to, therobot (100 a of FIG. 19 ), the vehicles (100 b-1 and 100 b-2 of FIG. 19), the XR device (100 c of FIG. 19 ), the hand-held device (100 d ofFIG. 19 ), the home appliance (100 e of FIG. 19 ), the IoT device (100 fof FIG. 19 ), a digital broadcasting terminal, a hologram device, apublic safety device, an MTC device, a medical device, a FinTech device(or a finance device), a security device, a climate/environment device,the AI server/device (400 of FIG. 19 ), the BSs (200 of FIG. 19 ), anetwork node, or the like. The wireless device may be mobile or fixedaccording to a use case/service.

In FIG. 21 , all of the various elements, components, units/portions,and/or modules in the wireless devices 100 and 200 may be connected toeach other through a wired interface or at least a part thereof may bewirelessly connected through the communication unit 110. For example, ineach of the wireless devices 100 and 200, the control unit 120 and thecommunication unit 110 may be connected by wire and the control unit 120and first units (e.g., 130 and 140) may be wirelessly connected throughthe communication unit 110. Each element, component, unit/portion,and/or module in the wireless devices 100 and 200 may further includeone or more elements. For example, the control unit 120 may beconfigured with a set of one or more processors. For example, thecontrol unit 120 may be configured with a set of a communication controlprocessor, an application processor, an electronic control unit (ECU), agraphical processing unit, and a memory control processor. In anotherexample, the memory 130 may be configured with a RAM, a dynamic RAM(DRAM), a ROM, a flash memory, a volatile memory, a non-volatile memory,and/or a combination thereof.

FIG. 22 illustrates a vehicle or an autonomous driving vehicle appliedto the present disclosure. The vehicle or autonomous driving vehicle maybe implemented as a mobile robot, a car, a train, a manned/unmannedaerial vehicle (AV), a ship, or the like.

Referring to FIG. 22 , a vehicle or autonomous driving vehicle 100 mayinclude an antenna unit 108, a communication unit 110, a control unit120, a driving unit 140 a, a power supply unit 140 b, a sensor unit 140c, and an autonomous driving unit 140 d. The antenna unit 108 may beconfigured as a part of the communication unit 110. The blocks110/130/140 a to 140 d correspond to the blocks 110/130/140 of FIG. 21 ,respectively.

The communication unit 110 may transmit and receive signals (e.g., dataand control signals) to and from external devices such as othervehicles, BSs (e.g., gNBs and road side units), and servers. The controlunit 120 may perform various operations by controlling elements of thevehicle or the autonomous driving vehicle 100. The control unit 120 mayinclude an ECU. The driving unit 140 a may enable the vehicle or theautonomous driving vehicle 100 to drive on a road. The driving unit 140a may include an engine, a motor, a powertrain, a wheel, a brake, asteering device, and so on. The power supply unit 140 b may supply powerto the vehicle or the autonomous driving vehicle 100 and include awired/wireless charging circuit, a battery, and so on. The sensor unit140 c may acquire information about a vehicle state, ambient environmentinformation, user information, and so on. The sensor unit 140 c mayinclude an inertial measurement unit (IMU) sensor, a collision sensor, awheel sensor, a speed sensor, a slope sensor, a weight sensor, a headingsensor, a position module, a vehicle forward/backward sensor, a batterysensor, a fuel sensor, a tire sensor, a steering sensor, a temperaturesensor, a humidity sensor, an ultrasonic sensor, an illumination sensor,a pedal position sensor, and so on. The autonomous driving unit 140 dmay implement technology for maintaining a lane on which the vehicle isdriving, technology for automatically adjusting speed, such as adaptivecruise control, technology for autonomously driving along a determinedpath, technology for driving by automatically setting a route if adestination is set, and the like.

For example, the communication unit 110 may receive map data, trafficinformation data, and so on from an external server. The autonomousdriving unit 140 d may generate an autonomous driving route and adriving plan from the obtained data. The control unit 120 may controlthe driving unit 140 a such that the vehicle or autonomous drivingvehicle 100 may move along the autonomous driving route according to thedriving plan (e.g., speed/direction control). During autonomous driving,the communication unit 110 may aperiodically/periodically acquire recenttraffic information data from the external server and acquiresurrounding traffic information data from neighboring vehicles. Duringautonomous driving, the sensor unit 140 c may obtain information about avehicle state and/or surrounding environment information. The autonomousdriving unit 140 d may update the autonomous driving route and thedriving plan based on the newly obtained data/information. Thecommunication unit 110 may transfer information about a vehicleposition, the autonomous driving route, and/or the driving plan to theexternal server. The external server may predict traffic informationdata using AI technology based on the information collected fromvehicles or autonomous driving vehicles and provide the predictedtraffic information data to the vehicles or the autonomous drivingvehicles.

The embodiments of the present disclosure described above arecombinations of elements and features of the present disclosure. Theelements or features may be considered selective unless otherwisementioned. Each element or feature may be practiced without beingcombined with other elements or features. Further, an embodiment of thepresent disclosure may be constructed by combining parts of the elementsand/or features. Operation orders described in embodiments of thepresent disclosure may be rearranged. Some constructions of any oneembodiment may be included in another embodiment and may be replacedwith corresponding constructions of another embodiment. It is obvious tothose skilled in the art that claims that are not explicitly cited ineach other in the appended claims may be presented in combination as anembodiment of the present disclosure or included as a new claim by asubsequent amendment after the application is filed.

The embodiments of the present disclosure have been described above,focusing on the signal transmission and reception relationship between aUE and a BS. The signal transmission and reception relationship isextended to signal transmission and reception between a UE and a relayor between a BS and a relay in the same manner or a similar manner. Aspecific operation described as performed by a BS may be performed by anupper node of the BS. Namely, it is apparent that, in a networkcomprised of a plurality of network nodes including a BS, variousoperations performed for communication with a UE may be performed by theBS, or network nodes other than the BS. The term BS may be replaced withthe term fixed station, Node B, enhanced Node B (eNode B or eNB), accesspoint, and so on. Further, the term UE may be replaced with the termterminal, mobile station (MS), mobile subscriber station (MSS), and soon.

Those skilled in the art will appreciate that the present disclosure maybe carried out in other specific ways than those set forth hereinwithout departing from the spirit and essential characteristics of thepresent disclosure. The above embodiments are therefore to be construedin all aspects as illustrative and not restrictive. The scope of thedisclosure should be determined by the appended claims and their legalequivalents, not by the above description, and all changes coming withinthe meaning and equivalency range of the appended claims are intended tobe embraced therein.

INDUSTRIAL APPLICABILITY

The present disclosure may be used in a UE, a BS, or other devices in amobile communication system.

What is claimed is:
 1. A method performed of transmitting a PhysicalUplink Shared Channel (PUSCH) by a user equipment (UE) in a wirelesscommunication system, the method comprising: receiving (i) firstinformation related to a start symbol of the PUSCH and (ii) secondinformation related to a start position for a PUSCH transmission; andtransmitting the PUSCH based on the first information, wherein aninterval for cyclic prefix extension (CPE) preceding the start symbol ofthe PUSCH is determined based on the second information, and wherein theinterval for CPE is equal to or less than a length of one orthogonalfrequency-division multiplexing (OFDM) symbol.
 2. The method of claim 1,wherein the length of one OFDM symbol is determined based on asubcarrier spacing (SCS).
 3. The method of claim 1, wherein the secondinformation is determined based on a subcarrier spacing (SCS).
 4. Themethod of claim 3, wherein the second information is used for informinga Channel Access Type for the PUSCH.
 5. The method of claim 1, whereinthe interval for the CPE is determined based on the second informationand a timing advance (TA).
 6. The method of claim 1, wherein the PUSCHis transmitted in an unlicensed band.
 7. A user equipment (UE) oftransmitting a Physical Uplink Shared Channel (PUSCH) in a wirelesscommunication system, the UE comprising: at least one transceiver; atleast one processor; and at least one computer memory operablyconnectable to the at least one processor and storing instructions that,when executed, cause the at least one processor to perform operationscomprising: receiving, through the at least one transceiver, (i) firstinformation related to a start symbol of the PUSCH and (ii) secondinformation related to a start position for a PUSCH transmission; andtransmitting, through the at least one transceiver, the PUSCH based onthe first information, wherein an interval for cyclic prefix extension(CPE) preceding the start symbol of the PUSCH is determined based on thesecond information, and wherein the interval for CPE is equal to or lessthan a length of one orthogonal frequency-division multiplexing (OFDM)symbol.
 8. The UE of claim 7, wherein the UE includes an autonomousdriving vehicle communicative with at least one of a network or anotherautonomous driving vehicle other than the UE.
 9. An apparatus oftransmitting a Physical Uplink Shared Channel (PUSCH), the apparatuscomprising: at least one processor; and at least one computer memoryoperably connectable to the at least one processor and storinginstructions that, when executed, cause the at least one processor toperform operations comprising: receiving (i) first information relatedto a start symbol of the PUSCH and (ii) second information related to astart position for a PUSCH transmission; and transmitting the PUSCHbased on the first information, wherein an interval for cyclic prefixextension (CPE) preceding the start symbol of the PUSCH is determinedbased on the second information, and wherein the interval for CPE isequal to or less than a length of one orthogonal frequency-divisionmultiplexing (OFDM) symbol.
 10. A non-transitory computer readablestorage medium storing at least one computer program comprisinginstructions that, when executed by at least one processor, cause the atleast one processor to perform operations, the operations comprising:receiving (i) first information related to a start symbol of the PUSCHand (ii) second information related to a start position for a PUSCHtransmission; and transmitting the PUSCH based on the first information,wherein an interval for cyclic prefix extension (CPE) preceding thestart symbol of the PUSCH is determined based on the second information,and wherein the interval for CPE is equal to or less than a length ofone orthogonal frequency-division multiplexing (OFDM) symbol.